2cos (problem 3.3.5)

Percentage Accurate: 52.8% → 99.8%
Time: 18.6s
Alternatives: 15
Speedup: 25.9×

Specification

?
\[\left(\left(-10000 \leq x \land x \leq 10000\right) \land 10^{-16} \cdot \left|x\right| < \varepsilon\right) \land \varepsilon < \left|x\right|\]
\[\begin{array}{l} \\ \cos \left(x + \varepsilon\right) - \cos x \end{array} \]
(FPCore (x eps) :precision binary64 (- (cos (+ x eps)) (cos x)))
double code(double x, double eps) {
	return cos((x + eps)) - cos(x);
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = cos((x + eps)) - cos(x)
end function
public static double code(double x, double eps) {
	return Math.cos((x + eps)) - Math.cos(x);
}
def code(x, eps):
	return math.cos((x + eps)) - math.cos(x)
function code(x, eps)
	return Float64(cos(Float64(x + eps)) - cos(x))
end
function tmp = code(x, eps)
	tmp = cos((x + eps)) - cos(x);
end
code[x_, eps_] := N[(N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Cos[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\cos \left(x + \varepsilon\right) - \cos x
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 15 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 52.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \cos \left(x + \varepsilon\right) - \cos x \end{array} \]
(FPCore (x eps) :precision binary64 (- (cos (+ x eps)) (cos x)))
double code(double x, double eps) {
	return cos((x + eps)) - cos(x);
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = cos((x + eps)) - cos(x)
end function
public static double code(double x, double eps) {
	return Math.cos((x + eps)) - Math.cos(x);
}
def code(x, eps):
	return math.cos((x + eps)) - math.cos(x)
function code(x, eps)
	return Float64(cos(Float64(x + eps)) - cos(x))
end
function tmp = code(x, eps)
	tmp = cos((x + eps)) - cos(x);
end
code[x_, eps_] := N[(N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Cos[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\cos \left(x + \varepsilon\right) - \cos x
\end{array}

Alternative 1: 99.8% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(\varepsilon \cdot 0.5\right)\\ \left(t\_0 \cdot \mathsf{fma}\left(\cos x, t\_0, \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right) \cdot -2 \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (sin (* eps 0.5))))
   (* (* t_0 (fma (cos x) t_0 (* (sin x) (cos (* eps 0.5))))) -2.0)))
double code(double x, double eps) {
	double t_0 = sin((eps * 0.5));
	return (t_0 * fma(cos(x), t_0, (sin(x) * cos((eps * 0.5))))) * -2.0;
}
function code(x, eps)
	t_0 = sin(Float64(eps * 0.5))
	return Float64(Float64(t_0 * fma(cos(x), t_0, Float64(sin(x) * cos(Float64(eps * 0.5))))) * -2.0)
end
code[x_, eps_] := Block[{t$95$0 = N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(N[(t$95$0 * N[(N[Cos[x], $MachinePrecision] * t$95$0 + N[(N[Sin[x], $MachinePrecision] * N[Cos[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(\varepsilon \cdot 0.5\right)\\
\left(t\_0 \cdot \mathsf{fma}\left(\cos x, t\_0, \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right) \cdot -2
\end{array}
\end{array}
Derivation
  1. Initial program 56.6%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
    2. lift-cos.f64N/A

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} - \cos x \]
    3. lift-cos.f64N/A

      \[\leadsto \cos \left(x + \varepsilon\right) - \color{blue}{\cos x} \]
    4. diff-cosN/A

      \[\leadsto \color{blue}{-2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    5. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
    6. lower-*.f64N/A

      \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
  4. Applied rewrites99.5%

    \[\leadsto \color{blue}{\left(\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \cdot -2} \]
  5. Step-by-step derivation
    1. lift-sin.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
    2. lift-*.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
    3. *-commutativeN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\frac{1}{2} \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \cdot -2 \]
    4. lift-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \color{blue}{\left(x + \left(x + \varepsilon\right)\right)}\right)\right) \cdot -2 \]
    5. lift-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \left(x + \color{blue}{\left(x + \varepsilon\right)}\right)\right)\right) \cdot -2 \]
    6. associate-+r+N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \cdot -2 \]
    7. distribute-rgt-inN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\left(x + x\right) \cdot \frac{1}{2} + \varepsilon \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
    8. +-rgt-identityN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right)\right) \cdot -2 \]
    9. lift-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right)\right) \cdot -2 \]
    10. lift-*.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right) \cdot \frac{1}{2}}\right)\right) \cdot -2 \]
    11. sin-sumN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) + \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)}\right) \cdot -2 \]
    12. lower-fma.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)}\right) \cdot -2 \]
    13. lower-sin.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\color{blue}{\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    14. lower-*.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \color{blue}{\left(\left(x + x\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    15. lower-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\color{blue}{\left(x + x\right)} \cdot \frac{1}{2}\right), \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    16. lower-cos.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \color{blue}{\cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    17. lift-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    18. +-rgt-identityN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\color{blue}{\varepsilon} \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    19. lift-sin.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\varepsilon \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
    20. lower-*.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
  6. Applied rewrites99.8%

    \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \color{blue}{\mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot 0.5\right), \cos \left(\varepsilon \cdot 0.5\right), \cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)}\right) \cdot -2 \]
  7. Taylor expanded in eps around inf

    \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right)} \cdot -2 \]
  8. Step-by-step derivation
    1. lower-*.f64N/A

      \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right)} \cdot -2 \]
    2. lower-sin.f64N/A

      \[\leadsto \left(\color{blue}{\sin \left(\frac{1}{2} \cdot \varepsilon\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    3. *-commutativeN/A

      \[\leadsto \left(\sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    4. lower-*.f64N/A

      \[\leadsto \left(\sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    5. lower-fma.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \color{blue}{\mathsf{fma}\left(\cos x, \sin \left(\frac{1}{2} \cdot \varepsilon\right), \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)}\right) \cdot -2 \]
    6. lower-cos.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\color{blue}{\cos x}, \sin \left(\frac{1}{2} \cdot \varepsilon\right), \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    7. lower-sin.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \color{blue}{\sin \left(\frac{1}{2} \cdot \varepsilon\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    8. *-commutativeN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    9. lower-*.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    10. *-commutativeN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
    11. lower-*.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
    12. lower-sin.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x} \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)\right)\right) \cdot -2 \]
    13. lower-cos.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \sin x \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
    14. *-commutativeN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \sin x \cdot \cos \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
    15. lower-*.f6499.8

      \[\leadsto \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \color{blue}{\left(\varepsilon \cdot 0.5\right)}\right)\right) \cdot -2 \]
  9. Applied rewrites99.8%

    \[\leadsto \color{blue}{\left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right)} \cdot -2 \]
  10. Add Preprocessing

Alternative 2: 99.6% accurate, 0.4× speedup?

\[\begin{array}{l} \\ -2 \cdot \left(\mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (*
  -2.0
  (*
   (fma (cos x) (sin (* eps 0.5)) (* (sin x) (cos (* eps 0.5))))
   (*
    eps
    (fma
     (* eps eps)
     (fma
      (* eps eps)
      (fma (* eps eps) -1.5500992063492063e-6 0.00026041666666666666)
      -0.020833333333333332)
     0.5)))))
double code(double x, double eps) {
	return -2.0 * (fma(cos(x), sin((eps * 0.5)), (sin(x) * cos((eps * 0.5)))) * (eps * fma((eps * eps), fma((eps * eps), fma((eps * eps), -1.5500992063492063e-6, 0.00026041666666666666), -0.020833333333333332), 0.5)));
}
function code(x, eps)
	return Float64(-2.0 * Float64(fma(cos(x), sin(Float64(eps * 0.5)), Float64(sin(x) * cos(Float64(eps * 0.5)))) * Float64(eps * fma(Float64(eps * eps), fma(Float64(eps * eps), fma(Float64(eps * eps), -1.5500992063492063e-6, 0.00026041666666666666), -0.020833333333333332), 0.5))))
end
code[x_, eps_] := N[(-2.0 * N[(N[(N[Cos[x], $MachinePrecision] * N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] + N[(N[Sin[x], $MachinePrecision] * N[Cos[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(eps * N[(N[(eps * eps), $MachinePrecision] * N[(N[(eps * eps), $MachinePrecision] * N[(N[(eps * eps), $MachinePrecision] * -1.5500992063492063e-6 + 0.00026041666666666666), $MachinePrecision] + -0.020833333333333332), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
-2 \cdot \left(\mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right)\right)
\end{array}
Derivation
  1. Initial program 56.6%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
    2. lift-cos.f64N/A

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} - \cos x \]
    3. lift-cos.f64N/A

      \[\leadsto \cos \left(x + \varepsilon\right) - \color{blue}{\cos x} \]
    4. diff-cosN/A

      \[\leadsto \color{blue}{-2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    5. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
    6. lower-*.f64N/A

      \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
  4. Applied rewrites99.5%

    \[\leadsto \color{blue}{\left(\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \cdot -2} \]
  5. Step-by-step derivation
    1. lift-sin.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
    2. lift-*.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
    3. *-commutativeN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\frac{1}{2} \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \cdot -2 \]
    4. lift-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \color{blue}{\left(x + \left(x + \varepsilon\right)\right)}\right)\right) \cdot -2 \]
    5. lift-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \left(x + \color{blue}{\left(x + \varepsilon\right)}\right)\right)\right) \cdot -2 \]
    6. associate-+r+N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \cdot -2 \]
    7. distribute-rgt-inN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\left(x + x\right) \cdot \frac{1}{2} + \varepsilon \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
    8. +-rgt-identityN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right)\right) \cdot -2 \]
    9. lift-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right)\right) \cdot -2 \]
    10. lift-*.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right) \cdot \frac{1}{2}}\right)\right) \cdot -2 \]
    11. sin-sumN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) + \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)}\right) \cdot -2 \]
    12. lower-fma.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)}\right) \cdot -2 \]
    13. lower-sin.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\color{blue}{\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    14. lower-*.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \color{blue}{\left(\left(x + x\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    15. lower-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\color{blue}{\left(x + x\right)} \cdot \frac{1}{2}\right), \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    16. lower-cos.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \color{blue}{\cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    17. lift-+.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    18. +-rgt-identityN/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\color{blue}{\varepsilon} \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    19. lift-sin.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\varepsilon \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
    20. lower-*.f64N/A

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
  6. Applied rewrites99.8%

    \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \color{blue}{\mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot 0.5\right), \cos \left(\varepsilon \cdot 0.5\right), \cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)}\right) \cdot -2 \]
  7. Taylor expanded in eps around inf

    \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right)} \cdot -2 \]
  8. Step-by-step derivation
    1. lower-*.f64N/A

      \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right)} \cdot -2 \]
    2. lower-sin.f64N/A

      \[\leadsto \left(\color{blue}{\sin \left(\frac{1}{2} \cdot \varepsilon\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    3. *-commutativeN/A

      \[\leadsto \left(\sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    4. lower-*.f64N/A

      \[\leadsto \left(\sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    5. lower-fma.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \color{blue}{\mathsf{fma}\left(\cos x, \sin \left(\frac{1}{2} \cdot \varepsilon\right), \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)}\right) \cdot -2 \]
    6. lower-cos.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\color{blue}{\cos x}, \sin \left(\frac{1}{2} \cdot \varepsilon\right), \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    7. lower-sin.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \color{blue}{\sin \left(\frac{1}{2} \cdot \varepsilon\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    8. *-commutativeN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    9. lower-*.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
    10. *-commutativeN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
    11. lower-*.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
    12. lower-sin.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x} \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)\right)\right) \cdot -2 \]
    13. lower-cos.f64N/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \sin x \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
    14. *-commutativeN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \sin x \cdot \cos \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
    15. lower-*.f6499.8

      \[\leadsto \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \color{blue}{\left(\varepsilon \cdot 0.5\right)}\right)\right) \cdot -2 \]
  9. Applied rewrites99.8%

    \[\leadsto \color{blue}{\left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right)} \cdot -2 \]
  10. Taylor expanded in eps around 0

    \[\leadsto \left(\left(\varepsilon \cdot \left(\frac{1}{2} + {\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) - \frac{1}{48}\right)\right)\right) \cdot \mathsf{fma}\left(\color{blue}{\cos x}, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \sin x \cdot \cos \left(\varepsilon \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
  11. Step-by-step derivation
    1. Applied rewrites99.7%

      \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right) \cdot \mathsf{fma}\left(\color{blue}{\cos x}, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right) \cdot -2 \]
    2. Final simplification99.7%

      \[\leadsto -2 \cdot \left(\mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right)\right) \]
    3. Add Preprocessing

    Alternative 3: 99.6% accurate, 0.5× speedup?

    \[\begin{array}{l} \\ -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.00026041666666666666, -0.020833333333333332\right), 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right) \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (*
      -2.0
      (*
       (sin (* eps 0.5))
       (fma
        (cos x)
        (*
         eps
         (fma
          eps
          (* eps (fma eps (* eps 0.00026041666666666666) -0.020833333333333332))
          0.5))
        (* (sin x) (cos (* eps 0.5)))))))
    double code(double x, double eps) {
    	return -2.0 * (sin((eps * 0.5)) * fma(cos(x), (eps * fma(eps, (eps * fma(eps, (eps * 0.00026041666666666666), -0.020833333333333332)), 0.5)), (sin(x) * cos((eps * 0.5)))));
    }
    
    function code(x, eps)
    	return Float64(-2.0 * Float64(sin(Float64(eps * 0.5)) * fma(cos(x), Float64(eps * fma(eps, Float64(eps * fma(eps, Float64(eps * 0.00026041666666666666), -0.020833333333333332)), 0.5)), Float64(sin(x) * cos(Float64(eps * 0.5))))))
    end
    
    code[x_, eps_] := N[(-2.0 * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[(N[Cos[x], $MachinePrecision] * N[(eps * N[(eps * N[(eps * N[(eps * N[(eps * 0.00026041666666666666), $MachinePrecision] + -0.020833333333333332), $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision] + N[(N[Sin[x], $MachinePrecision] * N[Cos[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.00026041666666666666, -0.020833333333333332\right), 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right)
    \end{array}
    
    Derivation
    1. Initial program 56.6%

      \[\cos \left(x + \varepsilon\right) - \cos x \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
      2. lift-cos.f64N/A

        \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} - \cos x \]
      3. lift-cos.f64N/A

        \[\leadsto \cos \left(x + \varepsilon\right) - \color{blue}{\cos x} \]
      4. diff-cosN/A

        \[\leadsto \color{blue}{-2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      5. *-commutativeN/A

        \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
      6. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
    4. Applied rewrites99.5%

      \[\leadsto \color{blue}{\left(\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \cdot -2} \]
    5. Step-by-step derivation
      1. lift-sin.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
      2. lift-*.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
      3. *-commutativeN/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\frac{1}{2} \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \cdot -2 \]
      4. lift-+.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \color{blue}{\left(x + \left(x + \varepsilon\right)\right)}\right)\right) \cdot -2 \]
      5. lift-+.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \left(x + \color{blue}{\left(x + \varepsilon\right)}\right)\right)\right) \cdot -2 \]
      6. associate-+r+N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\frac{1}{2} \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \cdot -2 \]
      7. distribute-rgt-inN/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \color{blue}{\left(\left(x + x\right) \cdot \frac{1}{2} + \varepsilon \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
      8. +-rgt-identityN/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right)\right) \cdot -2 \]
      9. lift-+.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right)\right) \cdot -2 \]
      10. lift-*.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(x + x\right) \cdot \frac{1}{2} + \color{blue}{\left(\varepsilon + 0\right) \cdot \frac{1}{2}}\right)\right) \cdot -2 \]
      11. sin-sumN/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) + \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)}\right) \cdot -2 \]
      12. lower-fma.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)}\right) \cdot -2 \]
      13. lower-sin.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\color{blue}{\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
      14. lower-*.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \color{blue}{\left(\left(x + x\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
      15. lower-+.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\color{blue}{\left(x + x\right)} \cdot \frac{1}{2}\right), \cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
      16. lower-cos.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \color{blue}{\cos \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}, \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
      17. lift-+.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\color{blue}{\left(\varepsilon + 0\right)} \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
      18. +-rgt-identityN/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\color{blue}{\varepsilon} \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
      19. lift-sin.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\varepsilon \cdot \frac{1}{2}\right), \cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
      20. lower-*.f64N/A

        \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot \frac{1}{2}\right), \cos \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\cos \left(\left(x + x\right) \cdot \frac{1}{2}\right) \cdot \sin \left(\left(\varepsilon + 0\right) \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
    6. Applied rewrites99.8%

      \[\leadsto \left(\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \color{blue}{\mathsf{fma}\left(\sin \left(\left(x + x\right) \cdot 0.5\right), \cos \left(\varepsilon \cdot 0.5\right), \cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)}\right) \cdot -2 \]
    7. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right)} \cdot -2 \]
    8. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right)} \cdot -2 \]
      2. lower-sin.f64N/A

        \[\leadsto \left(\color{blue}{\sin \left(\frac{1}{2} \cdot \varepsilon\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
      3. *-commutativeN/A

        \[\leadsto \left(\sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
      4. lower-*.f64N/A

        \[\leadsto \left(\sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)} \cdot \left(\cos x \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right) + \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
      5. lower-fma.f64N/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \color{blue}{\mathsf{fma}\left(\cos x, \sin \left(\frac{1}{2} \cdot \varepsilon\right), \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)}\right) \cdot -2 \]
      6. lower-cos.f64N/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\color{blue}{\cos x}, \sin \left(\frac{1}{2} \cdot \varepsilon\right), \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
      7. lower-sin.f64N/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \color{blue}{\sin \left(\frac{1}{2} \cdot \varepsilon\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
      8. *-commutativeN/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
      9. lower-*.f64N/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}, \cos \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin x\right)\right) \cdot -2 \]
      10. *-commutativeN/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
      11. lower-*.f64N/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
      12. lower-sin.f64N/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \color{blue}{\sin x} \cdot \cos \left(\frac{1}{2} \cdot \varepsilon\right)\right)\right) \cdot -2 \]
      13. lower-cos.f64N/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \sin x \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot \varepsilon\right)}\right)\right) \cdot -2 \]
      14. *-commutativeN/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot \frac{1}{2}\right), \sin x \cdot \cos \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}\right)\right) \cdot -2 \]
      15. lower-*.f6499.8

        \[\leadsto \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \color{blue}{\left(\varepsilon \cdot 0.5\right)}\right)\right) \cdot -2 \]
    9. Applied rewrites99.8%

      \[\leadsto \color{blue}{\left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \sin \left(\varepsilon \cdot 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right)} \cdot -2 \]
    10. Taylor expanded in eps around 0

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \mathsf{fma}\left(\cos x, \varepsilon \cdot \color{blue}{\left(\frac{1}{2} + {\varepsilon}^{2} \cdot \left(\frac{1}{3840} \cdot {\varepsilon}^{2} - \frac{1}{48}\right)\right)}, \sin x \cdot \cos \left(\varepsilon \cdot \frac{1}{2}\right)\right)\right) \cdot -2 \]
    11. Step-by-step derivation
      1. Applied rewrites99.6%

        \[\leadsto \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \varepsilon \cdot \color{blue}{\mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.00026041666666666666, -0.020833333333333332\right), 0.5\right)}, \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right) \cdot -2 \]
      2. Final simplification99.6%

        \[\leadsto -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \mathsf{fma}\left(\cos x, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.00026041666666666666, -0.020833333333333332\right), 0.5\right), \sin x \cdot \cos \left(\varepsilon \cdot 0.5\right)\right)\right) \]
      3. Add Preprocessing

      Alternative 4: 99.7% accurate, 0.9× speedup?

      \[\begin{array}{l} \\ -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)\right) \end{array} \]
      (FPCore (x eps)
       :precision binary64
       (* -2.0 (* (sin (* eps 0.5)) (sin (fma 0.5 eps x)))))
      double code(double x, double eps) {
      	return -2.0 * (sin((eps * 0.5)) * sin(fma(0.5, eps, x)));
      }
      
      function code(x, eps)
      	return Float64(-2.0 * Float64(sin(Float64(eps * 0.5)) * sin(fma(0.5, eps, x))))
      end
      
      code[x_, eps_] := N[(-2.0 * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[Sin[N[(0.5 * eps + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)\right)
      \end{array}
      
      Derivation
      1. Initial program 56.6%

        \[\cos \left(x + \varepsilon\right) - \cos x \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
        2. lift-cos.f64N/A

          \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} - \cos x \]
        3. lift-cos.f64N/A

          \[\leadsto \cos \left(x + \varepsilon\right) - \color{blue}{\cos x} \]
        4. diff-cosN/A

          \[\leadsto \color{blue}{-2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
        5. *-commutativeN/A

          \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
        6. lower-*.f64N/A

          \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
      4. Applied rewrites99.5%

        \[\leadsto \color{blue}{\left(\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \cdot -2} \]
      5. Taylor expanded in eps around inf

        \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \left(\varepsilon + 2 \cdot x\right)\right)\right)} \cdot -2 \]
      6. Step-by-step derivation
        1. metadata-evalN/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \left(\varepsilon + \color{blue}{\left(\mathsf{neg}\left(-2\right)\right)} \cdot x\right)\right)\right) \cdot -2 \]
        2. cancel-sign-sub-invN/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \color{blue}{\left(\varepsilon - -2 \cdot x\right)}\right)\right) \cdot -2 \]
        3. lower-*.f64N/A

          \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \left(\varepsilon - -2 \cdot x\right)\right)\right)} \cdot -2 \]
        4. lower-sin.f64N/A

          \[\leadsto \left(\color{blue}{\sin \left(\frac{1}{2} \cdot \varepsilon\right)} \cdot \sin \left(\frac{1}{2} \cdot \left(\varepsilon - -2 \cdot x\right)\right)\right) \cdot -2 \]
        5. lower-*.f64N/A

          \[\leadsto \left(\sin \color{blue}{\left(\frac{1}{2} \cdot \varepsilon\right)} \cdot \sin \left(\frac{1}{2} \cdot \left(\varepsilon - -2 \cdot x\right)\right)\right) \cdot -2 \]
        6. lower-sin.f64N/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \color{blue}{\sin \left(\frac{1}{2} \cdot \left(\varepsilon - -2 \cdot x\right)\right)}\right) \cdot -2 \]
        7. cancel-sign-sub-invN/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \color{blue}{\left(\varepsilon + \left(\mathsf{neg}\left(-2\right)\right) \cdot x\right)}\right)\right) \cdot -2 \]
        8. metadata-evalN/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \left(\varepsilon + \color{blue}{2} \cdot x\right)\right)\right) \cdot -2 \]
        9. distribute-lft-inN/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \color{blue}{\left(\frac{1}{2} \cdot \varepsilon + \frac{1}{2} \cdot \left(2 \cdot x\right)\right)}\right) \cdot -2 \]
        10. associate-*r*N/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon + \color{blue}{\left(\frac{1}{2} \cdot 2\right) \cdot x}\right)\right) \cdot -2 \]
        11. metadata-evalN/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon + \color{blue}{1} \cdot x\right)\right) \cdot -2 \]
        12. *-lft-identityN/A

          \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon + \color{blue}{x}\right)\right) \cdot -2 \]
        13. lower-fma.f6499.6

          \[\leadsto \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \color{blue}{\left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)}\right) \cdot -2 \]
      7. Applied rewrites99.6%

        \[\leadsto \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)\right)} \cdot -2 \]
      8. Final simplification99.6%

        \[\leadsto -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)\right) \]
      9. Add Preprocessing

      Alternative 5: 99.3% accurate, 0.9× speedup?

      \[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot -0.5\right) - \sin x\right) \end{array} \]
      (FPCore (x eps)
       :precision binary64
       (* eps (- (* eps (* (cos x) -0.5)) (sin x))))
      double code(double x, double eps) {
      	return eps * ((eps * (cos(x) * -0.5)) - sin(x));
      }
      
      real(8) function code(x, eps)
          real(8), intent (in) :: x
          real(8), intent (in) :: eps
          code = eps * ((eps * (cos(x) * (-0.5d0))) - sin(x))
      end function
      
      public static double code(double x, double eps) {
      	return eps * ((eps * (Math.cos(x) * -0.5)) - Math.sin(x));
      }
      
      def code(x, eps):
      	return eps * ((eps * (math.cos(x) * -0.5)) - math.sin(x))
      
      function code(x, eps)
      	return Float64(eps * Float64(Float64(eps * Float64(cos(x) * -0.5)) - sin(x)))
      end
      
      function tmp = code(x, eps)
      	tmp = eps * ((eps * (cos(x) * -0.5)) - sin(x));
      end
      
      code[x_, eps_] := N[(eps * N[(N[(eps * N[(N[Cos[x], $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot -0.5\right) - \sin x\right)
      \end{array}
      
      Derivation
      1. Initial program 56.6%

        \[\cos \left(x + \varepsilon\right) - \cos x \]
      2. Add Preprocessing
      3. Taylor expanded in eps around 0

        \[\leadsto \color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)} \]
      4. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)} \]
        2. *-commutativeN/A

          \[\leadsto \varepsilon \cdot \left(\color{blue}{\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2}} - \sin x\right) \]
        3. associate-*r*N/A

          \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right)} - \sin x\right) \]
        4. *-commutativeN/A

          \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
        5. lower--.f64N/A

          \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
        6. lower-*.f64N/A

          \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
        7. lower-*.f64N/A

          \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
        8. lower-cos.f64N/A

          \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \color{blue}{\cos x}\right) - \sin x\right) \]
        9. lower-sin.f6498.9

          \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \color{blue}{\sin x}\right) \]
      5. Applied rewrites98.9%

        \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
      6. Final simplification98.9%

        \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot -0.5\right) - \sin x\right) \]
      7. Add Preprocessing

      Alternative 6: 98.9% accurate, 1.7× speedup?

      \[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right) - \sin x\right) \end{array} \]
      (FPCore (x eps)
       :precision binary64
       (* eps (- (* eps (fma eps (* eps 0.041666666666666664) -0.5)) (sin x))))
      double code(double x, double eps) {
      	return eps * ((eps * fma(eps, (eps * 0.041666666666666664), -0.5)) - sin(x));
      }
      
      function code(x, eps)
      	return Float64(eps * Float64(Float64(eps * fma(eps, Float64(eps * 0.041666666666666664), -0.5)) - sin(x)))
      end
      
      code[x_, eps_] := N[(eps * N[(N[(eps * N[(eps * N[(eps * 0.041666666666666664), $MachinePrecision] + -0.5), $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \varepsilon \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right) - \sin x\right)
      \end{array}
      
      Derivation
      1. Initial program 56.6%

        \[\cos \left(x + \varepsilon\right) - \cos x \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
        2. sub-negN/A

          \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
        3. lift-cos.f64N/A

          \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
        4. lift-+.f64N/A

          \[\leadsto \cos \color{blue}{\left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
        5. cos-sumN/A

          \[\leadsto \color{blue}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
        6. associate-+l-N/A

          \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
        7. lower--.f64N/A

          \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
        8. lift-cos.f64N/A

          \[\leadsto \color{blue}{\cos x} \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
        9. lower-*.f64N/A

          \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
        10. lower-cos.f64N/A

          \[\leadsto \cos x \cdot \color{blue}{\cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
        11. flip--N/A

          \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \left(\mathsf{neg}\left(\cos x\right)\right) \cdot \left(\mathsf{neg}\left(\cos x\right)\right)}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)}} \]
        12. sqr-negN/A

          \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \color{blue}{\cos x \cdot \cos x}}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
        13. sub-negN/A

          \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \cos x \cdot \cos x}{\color{blue}{\sin x \cdot \sin \varepsilon - \cos x}} \]
        14. flip-+N/A

          \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\left(\sin x \cdot \sin \varepsilon + \cos x\right)} \]
        15. lower-fma.f64N/A

          \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
        16. lower-sin.f64N/A

          \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\color{blue}{\sin x}, \sin \varepsilon, \cos x\right) \]
        17. lower-sin.f6456.8

          \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \color{blue}{\sin \varepsilon}, \cos x\right) \]
      4. Applied rewrites56.8%

        \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
      5. Taylor expanded in eps around 0

        \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
      6. Applied rewrites99.3%

        \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \sin x \cdot 0.16666666666666666, \cos x \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right)\right) - \sin x\right)} \]
      7. Taylor expanded in x around 0

        \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{1}{24} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) - \sin \color{blue}{x}\right) \]
      8. Step-by-step derivation
        1. Applied rewrites98.5%

          \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right) - \sin \color{blue}{x}\right) \]
        2. Add Preprocessing

        Alternative 7: 98.9% accurate, 1.8× speedup?

        \[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot -0.5 - \sin x\right) \end{array} \]
        (FPCore (x eps) :precision binary64 (* eps (- (* eps -0.5) (sin x))))
        double code(double x, double eps) {
        	return eps * ((eps * -0.5) - sin(x));
        }
        
        real(8) function code(x, eps)
            real(8), intent (in) :: x
            real(8), intent (in) :: eps
            code = eps * ((eps * (-0.5d0)) - sin(x))
        end function
        
        public static double code(double x, double eps) {
        	return eps * ((eps * -0.5) - Math.sin(x));
        }
        
        def code(x, eps):
        	return eps * ((eps * -0.5) - math.sin(x))
        
        function code(x, eps)
        	return Float64(eps * Float64(Float64(eps * -0.5) - sin(x)))
        end
        
        function tmp = code(x, eps)
        	tmp = eps * ((eps * -0.5) - sin(x));
        end
        
        code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \varepsilon \cdot \left(\varepsilon \cdot -0.5 - \sin x\right)
        \end{array}
        
        Derivation
        1. Initial program 56.6%

          \[\cos \left(x + \varepsilon\right) - \cos x \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift--.f64N/A

            \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
          2. sub-negN/A

            \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
          3. lift-cos.f64N/A

            \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
          4. lift-+.f64N/A

            \[\leadsto \cos \color{blue}{\left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
          5. cos-sumN/A

            \[\leadsto \color{blue}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
          6. associate-+l-N/A

            \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
          7. lower--.f64N/A

            \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
          8. lift-cos.f64N/A

            \[\leadsto \color{blue}{\cos x} \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
          9. lower-*.f64N/A

            \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
          10. lower-cos.f64N/A

            \[\leadsto \cos x \cdot \color{blue}{\cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
          11. flip--N/A

            \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \left(\mathsf{neg}\left(\cos x\right)\right) \cdot \left(\mathsf{neg}\left(\cos x\right)\right)}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)}} \]
          12. sqr-negN/A

            \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \color{blue}{\cos x \cdot \cos x}}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
          13. sub-negN/A

            \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \cos x \cdot \cos x}{\color{blue}{\sin x \cdot \sin \varepsilon - \cos x}} \]
          14. flip-+N/A

            \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\left(\sin x \cdot \sin \varepsilon + \cos x\right)} \]
          15. lower-fma.f64N/A

            \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
          16. lower-sin.f64N/A

            \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\color{blue}{\sin x}, \sin \varepsilon, \cos x\right) \]
          17. lower-sin.f6456.8

            \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \color{blue}{\sin \varepsilon}, \cos x\right) \]
        4. Applied rewrites56.8%

          \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
        5. Taylor expanded in eps around 0

          \[\leadsto \color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)} \]
        6. Step-by-step derivation
          1. sub-negN/A

            \[\leadsto \varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) + \left(\mathsf{neg}\left(\sin x\right)\right)\right)} \]
          2. *-commutativeN/A

            \[\leadsto \varepsilon \cdot \left(\color{blue}{\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2}} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
          3. associate-*r*N/A

            \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right)} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
          4. *-commutativeN/A

            \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
          5. sin-negN/A

            \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \color{blue}{\sin \left(\mathsf{neg}\left(x\right)\right)}\right) \]
          6. +-commutativeN/A

            \[\leadsto \varepsilon \cdot \color{blue}{\left(\sin \left(\mathsf{neg}\left(x\right)\right) + \varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right)} \]
          7. lower-*.f64N/A

            \[\leadsto \color{blue}{\varepsilon \cdot \left(\sin \left(\mathsf{neg}\left(x\right)\right) + \varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right)} \]
          8. +-commutativeN/A

            \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \sin \left(\mathsf{neg}\left(x\right)\right)\right)} \]
          9. sin-negN/A

            \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \color{blue}{\left(\mathsf{neg}\left(\sin x\right)\right)}\right) \]
          10. sub-negN/A

            \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
          11. lower--.f64N/A

            \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
          12. lower-*.f64N/A

            \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
          13. lower-*.f64N/A

            \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
          14. lower-cos.f64N/A

            \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \color{blue}{\cos x}\right) - \sin x\right) \]
          15. lower-sin.f6498.9

            \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \color{blue}{\sin x}\right) \]
        7. Applied rewrites98.9%

          \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
        8. Taylor expanded in x around 0

          \[\leadsto \varepsilon \cdot \left(\frac{-1}{2} \cdot \varepsilon - \sin \color{blue}{x}\right) \]
        9. Step-by-step derivation
          1. Applied rewrites98.5%

            \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot -0.5 - \sin \color{blue}{x}\right) \]
          2. Add Preprocessing

          Alternative 8: 98.3% accurate, 2.1× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} t_0 := \varepsilon \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right)\right)\\ \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, x \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.027777777777777776, 0.16666666666666666\right), -0.5 \cdot t\_0\right), \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.16666666666666666, -1\right)\right), t\_0\right) \end{array} \end{array} \]
          (FPCore (x eps)
           :precision binary64
           (let* ((t_0 (* eps (* eps (fma eps (* eps 0.041666666666666664) -0.5)))))
             (fma
              x
              (fma
               x
               (fma
                eps
                (* x (fma (* eps eps) -0.027777777777777776 0.16666666666666666))
                (* -0.5 t_0))
               (* eps (fma eps (* eps 0.16666666666666666) -1.0)))
              t_0)))
          double code(double x, double eps) {
          	double t_0 = eps * (eps * fma(eps, (eps * 0.041666666666666664), -0.5));
          	return fma(x, fma(x, fma(eps, (x * fma((eps * eps), -0.027777777777777776, 0.16666666666666666)), (-0.5 * t_0)), (eps * fma(eps, (eps * 0.16666666666666666), -1.0))), t_0);
          }
          
          function code(x, eps)
          	t_0 = Float64(eps * Float64(eps * fma(eps, Float64(eps * 0.041666666666666664), -0.5)))
          	return fma(x, fma(x, fma(eps, Float64(x * fma(Float64(eps * eps), -0.027777777777777776, 0.16666666666666666)), Float64(-0.5 * t_0)), Float64(eps * fma(eps, Float64(eps * 0.16666666666666666), -1.0))), t_0)
          end
          
          code[x_, eps_] := Block[{t$95$0 = N[(eps * N[(eps * N[(eps * N[(eps * 0.041666666666666664), $MachinePrecision] + -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(x * N[(x * N[(eps * N[(x * N[(N[(eps * eps), $MachinePrecision] * -0.027777777777777776 + 0.16666666666666666), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * t$95$0), $MachinePrecision]), $MachinePrecision] + N[(eps * N[(eps * N[(eps * 0.16666666666666666), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$0), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          t_0 := \varepsilon \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right)\right)\\
          \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, x \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.027777777777777776, 0.16666666666666666\right), -0.5 \cdot t\_0\right), \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.16666666666666666, -1\right)\right), t\_0\right)
          \end{array}
          \end{array}
          
          Derivation
          1. Initial program 56.6%

            \[\cos \left(x + \varepsilon\right) - \cos x \]
          2. Add Preprocessing
          3. Taylor expanded in eps around 0

            \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
          4. Step-by-step derivation
            1. lower-*.f64N/A

              \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
            2. sub-negN/A

              \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) + \left(\mathsf{neg}\left(\sin x\right)\right)\right)} \]
            3. lower-fma.f64N/A

              \[\leadsto \varepsilon \cdot \color{blue}{\mathsf{fma}\left(\varepsilon, \frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right), \mathsf{neg}\left(\sin x\right)\right)} \]
          5. Applied rewrites99.3%

            \[\leadsto \color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\cos x, -0.5 + \varepsilon \cdot \left(\varepsilon \cdot 0.041666666666666664\right), \varepsilon \cdot \left(0.16666666666666666 \cdot \sin x\right)\right), \sin \left(-x\right)\right)} \]
          6. Taylor expanded in x around 0

            \[\leadsto x \cdot \left(\varepsilon \cdot \left(\frac{1}{6} \cdot {\varepsilon}^{2} - 1\right) + x \cdot \left(\frac{-1}{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{1}{24} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)\right) + \varepsilon \cdot \left(x \cdot \left(\frac{1}{6} + \frac{-1}{36} \cdot {\varepsilon}^{2}\right)\right)\right)\right) + \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{1}{24} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
          7. Step-by-step derivation
            1. Applied rewrites98.0%

              \[\leadsto \mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, x \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.027777777777777776, 0.16666666666666666\right), -0.5 \cdot \left(\varepsilon \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right)\right)\right)\right), \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.16666666666666666, -1\right)\right)}, \varepsilon \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right)\right)\right) \]
            2. Add Preprocessing

            Alternative 9: 98.3% accurate, 4.5× speedup?

            \[\begin{array}{l} \\ \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, x \cdot 0.16666666666666666, \varepsilon \cdot \left(\varepsilon \cdot 0.25\right)\right), -\varepsilon\right), \left(\varepsilon \cdot \varepsilon\right) \cdot -0.5\right) \end{array} \]
            (FPCore (x eps)
             :precision binary64
             (fma
              x
              (fma x (fma eps (* x 0.16666666666666666) (* eps (* eps 0.25))) (- eps))
              (* (* eps eps) -0.5)))
            double code(double x, double eps) {
            	return fma(x, fma(x, fma(eps, (x * 0.16666666666666666), (eps * (eps * 0.25))), -eps), ((eps * eps) * -0.5));
            }
            
            function code(x, eps)
            	return fma(x, fma(x, fma(eps, Float64(x * 0.16666666666666666), Float64(eps * Float64(eps * 0.25))), Float64(-eps)), Float64(Float64(eps * eps) * -0.5))
            end
            
            code[x_, eps_] := N[(x * N[(x * N[(eps * N[(x * 0.16666666666666666), $MachinePrecision] + N[(eps * N[(eps * 0.25), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + (-eps)), $MachinePrecision] + N[(N[(eps * eps), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, x \cdot 0.16666666666666666, \varepsilon \cdot \left(\varepsilon \cdot 0.25\right)\right), -\varepsilon\right), \left(\varepsilon \cdot \varepsilon\right) \cdot -0.5\right)
            \end{array}
            
            Derivation
            1. Initial program 56.6%

              \[\cos \left(x + \varepsilon\right) - \cos x \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift--.f64N/A

                \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
              2. sub-negN/A

                \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
              3. lift-cos.f64N/A

                \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
              4. lift-+.f64N/A

                \[\leadsto \cos \color{blue}{\left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
              5. cos-sumN/A

                \[\leadsto \color{blue}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
              6. associate-+l-N/A

                \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
              7. lower--.f64N/A

                \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
              8. lift-cos.f64N/A

                \[\leadsto \color{blue}{\cos x} \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
              9. lower-*.f64N/A

                \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
              10. lower-cos.f64N/A

                \[\leadsto \cos x \cdot \color{blue}{\cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
              11. flip--N/A

                \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \left(\mathsf{neg}\left(\cos x\right)\right) \cdot \left(\mathsf{neg}\left(\cos x\right)\right)}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)}} \]
              12. sqr-negN/A

                \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \color{blue}{\cos x \cdot \cos x}}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
              13. sub-negN/A

                \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \cos x \cdot \cos x}{\color{blue}{\sin x \cdot \sin \varepsilon - \cos x}} \]
              14. flip-+N/A

                \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\left(\sin x \cdot \sin \varepsilon + \cos x\right)} \]
              15. lower-fma.f64N/A

                \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
              16. lower-sin.f64N/A

                \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\color{blue}{\sin x}, \sin \varepsilon, \cos x\right) \]
              17. lower-sin.f6456.8

                \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \color{blue}{\sin \varepsilon}, \cos x\right) \]
            4. Applied rewrites56.8%

              \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
            5. Taylor expanded in eps around 0

              \[\leadsto \color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)} \]
            6. Step-by-step derivation
              1. sub-negN/A

                \[\leadsto \varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) + \left(\mathsf{neg}\left(\sin x\right)\right)\right)} \]
              2. *-commutativeN/A

                \[\leadsto \varepsilon \cdot \left(\color{blue}{\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2}} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
              3. associate-*r*N/A

                \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right)} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
              4. *-commutativeN/A

                \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
              5. sin-negN/A

                \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \color{blue}{\sin \left(\mathsf{neg}\left(x\right)\right)}\right) \]
              6. +-commutativeN/A

                \[\leadsto \varepsilon \cdot \color{blue}{\left(\sin \left(\mathsf{neg}\left(x\right)\right) + \varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right)} \]
              7. lower-*.f64N/A

                \[\leadsto \color{blue}{\varepsilon \cdot \left(\sin \left(\mathsf{neg}\left(x\right)\right) + \varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right)} \]
              8. +-commutativeN/A

                \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \sin \left(\mathsf{neg}\left(x\right)\right)\right)} \]
              9. sin-negN/A

                \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \color{blue}{\left(\mathsf{neg}\left(\sin x\right)\right)}\right) \]
              10. sub-negN/A

                \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
              11. lower--.f64N/A

                \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
              12. lower-*.f64N/A

                \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
              13. lower-*.f64N/A

                \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
              14. lower-cos.f64N/A

                \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \color{blue}{\cos x}\right) - \sin x\right) \]
              15. lower-sin.f6498.9

                \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \color{blue}{\sin x}\right) \]
            7. Applied rewrites98.9%

              \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
            8. Taylor expanded in x around 0

              \[\leadsto \frac{-1}{2} \cdot {\varepsilon}^{2} + \color{blue}{x \cdot \left(-1 \cdot \varepsilon + x \cdot \left(\frac{1}{6} \cdot \left(\varepsilon \cdot x\right) + \frac{1}{4} \cdot {\varepsilon}^{2}\right)\right)} \]
            9. Step-by-step derivation
              1. Applied rewrites97.9%

                \[\leadsto \mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, x \cdot 0.16666666666666666, \varepsilon \cdot \left(\varepsilon \cdot 0.25\right)\right), -\varepsilon\right)}, -0.5 \cdot \left(\varepsilon \cdot \varepsilon\right)\right) \]
              2. Final simplification97.9%

                \[\leadsto \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, x \cdot 0.16666666666666666, \varepsilon \cdot \left(\varepsilon \cdot 0.25\right)\right), -\varepsilon\right), \left(\varepsilon \cdot \varepsilon\right) \cdot -0.5\right) \]
              3. Add Preprocessing

              Alternative 10: 98.1% accurate, 6.1× speedup?

              \[\begin{array}{l} \\ \varepsilon \cdot \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, 0.25, x \cdot 0.16666666666666666\right), -1\right), \varepsilon \cdot -0.5\right) \end{array} \]
              (FPCore (x eps)
               :precision binary64
               (*
                eps
                (fma x (fma x (fma eps 0.25 (* x 0.16666666666666666)) -1.0) (* eps -0.5))))
              double code(double x, double eps) {
              	return eps * fma(x, fma(x, fma(eps, 0.25, (x * 0.16666666666666666)), -1.0), (eps * -0.5));
              }
              
              function code(x, eps)
              	return Float64(eps * fma(x, fma(x, fma(eps, 0.25, Float64(x * 0.16666666666666666)), -1.0), Float64(eps * -0.5)))
              end
              
              code[x_, eps_] := N[(eps * N[(x * N[(x * N[(eps * 0.25 + N[(x * 0.16666666666666666), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision] + N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \varepsilon \cdot \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, 0.25, x \cdot 0.16666666666666666\right), -1\right), \varepsilon \cdot -0.5\right)
              \end{array}
              
              Derivation
              1. Initial program 56.6%

                \[\cos \left(x + \varepsilon\right) - \cos x \]
              2. Add Preprocessing
              3. Step-by-step derivation
                1. lift--.f64N/A

                  \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
                2. sub-negN/A

                  \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
                3. lift-cos.f64N/A

                  \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
                4. lift-+.f64N/A

                  \[\leadsto \cos \color{blue}{\left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
                5. cos-sumN/A

                  \[\leadsto \color{blue}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
                6. associate-+l-N/A

                  \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
                7. lower--.f64N/A

                  \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
                8. lift-cos.f64N/A

                  \[\leadsto \color{blue}{\cos x} \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
                9. lower-*.f64N/A

                  \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
                10. lower-cos.f64N/A

                  \[\leadsto \cos x \cdot \color{blue}{\cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
                11. flip--N/A

                  \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \left(\mathsf{neg}\left(\cos x\right)\right) \cdot \left(\mathsf{neg}\left(\cos x\right)\right)}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)}} \]
                12. sqr-negN/A

                  \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \color{blue}{\cos x \cdot \cos x}}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
                13. sub-negN/A

                  \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \cos x \cdot \cos x}{\color{blue}{\sin x \cdot \sin \varepsilon - \cos x}} \]
                14. flip-+N/A

                  \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\left(\sin x \cdot \sin \varepsilon + \cos x\right)} \]
                15. lower-fma.f64N/A

                  \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
                16. lower-sin.f64N/A

                  \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\color{blue}{\sin x}, \sin \varepsilon, \cos x\right) \]
                17. lower-sin.f6456.8

                  \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \color{blue}{\sin \varepsilon}, \cos x\right) \]
              4. Applied rewrites56.8%

                \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
              5. Taylor expanded in eps around 0

                \[\leadsto \color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)} \]
              6. Step-by-step derivation
                1. sub-negN/A

                  \[\leadsto \varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) + \left(\mathsf{neg}\left(\sin x\right)\right)\right)} \]
                2. *-commutativeN/A

                  \[\leadsto \varepsilon \cdot \left(\color{blue}{\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2}} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
                3. associate-*r*N/A

                  \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right)} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
                4. *-commutativeN/A

                  \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
                5. sin-negN/A

                  \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \color{blue}{\sin \left(\mathsf{neg}\left(x\right)\right)}\right) \]
                6. +-commutativeN/A

                  \[\leadsto \varepsilon \cdot \color{blue}{\left(\sin \left(\mathsf{neg}\left(x\right)\right) + \varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right)} \]
                7. lower-*.f64N/A

                  \[\leadsto \color{blue}{\varepsilon \cdot \left(\sin \left(\mathsf{neg}\left(x\right)\right) + \varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right)} \]
                8. +-commutativeN/A

                  \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \sin \left(\mathsf{neg}\left(x\right)\right)\right)} \]
                9. sin-negN/A

                  \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \color{blue}{\left(\mathsf{neg}\left(\sin x\right)\right)}\right) \]
                10. sub-negN/A

                  \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
                11. lower--.f64N/A

                  \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
                12. lower-*.f64N/A

                  \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                13. lower-*.f64N/A

                  \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                14. lower-cos.f64N/A

                  \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \color{blue}{\cos x}\right) - \sin x\right) \]
                15. lower-sin.f6498.9

                  \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \color{blue}{\sin x}\right) \]
              7. Applied rewrites98.9%

                \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
              8. Taylor expanded in x around 0

                \[\leadsto \varepsilon \cdot \left(\frac{-1}{2} \cdot \varepsilon + \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)}\right) \]
              9. Step-by-step derivation
                1. Applied rewrites97.8%

                  \[\leadsto \varepsilon \cdot \mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, 0.25, x \cdot 0.16666666666666666\right), -1\right)}, \varepsilon \cdot -0.5\right) \]
                2. Add Preprocessing

                Alternative 11: 97.6% accurate, 7.4× speedup?

                \[\begin{array}{l} \\ \varepsilon \cdot \mathsf{fma}\left(x, \mathsf{fma}\left(0.25, \varepsilon \cdot x, -1\right), \varepsilon \cdot -0.5\right) \end{array} \]
                (FPCore (x eps)
                 :precision binary64
                 (* eps (fma x (fma 0.25 (* eps x) -1.0) (* eps -0.5))))
                double code(double x, double eps) {
                	return eps * fma(x, fma(0.25, (eps * x), -1.0), (eps * -0.5));
                }
                
                function code(x, eps)
                	return Float64(eps * fma(x, fma(0.25, Float64(eps * x), -1.0), Float64(eps * -0.5)))
                end
                
                code[x_, eps_] := N[(eps * N[(x * N[(0.25 * N[(eps * x), $MachinePrecision] + -1.0), $MachinePrecision] + N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \varepsilon \cdot \mathsf{fma}\left(x, \mathsf{fma}\left(0.25, \varepsilon \cdot x, -1\right), \varepsilon \cdot -0.5\right)
                \end{array}
                
                Derivation
                1. Initial program 56.6%

                  \[\cos \left(x + \varepsilon\right) - \cos x \]
                2. Add Preprocessing
                3. Step-by-step derivation
                  1. lift--.f64N/A

                    \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
                  2. sub-negN/A

                    \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
                  3. lift-cos.f64N/A

                    \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
                  4. lift-+.f64N/A

                    \[\leadsto \cos \color{blue}{\left(x + \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
                  5. cos-sumN/A

                    \[\leadsto \color{blue}{\left(\cos x \cdot \cos \varepsilon - \sin x \cdot \sin \varepsilon\right)} + \left(\mathsf{neg}\left(\cos x\right)\right) \]
                  6. associate-+l-N/A

                    \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
                  7. lower--.f64N/A

                    \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right)} \]
                  8. lift-cos.f64N/A

                    \[\leadsto \color{blue}{\cos x} \cdot \cos \varepsilon - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
                  9. lower-*.f64N/A

                    \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
                  10. lower-cos.f64N/A

                    \[\leadsto \cos x \cdot \color{blue}{\cos \varepsilon} - \left(\sin x \cdot \sin \varepsilon - \left(\mathsf{neg}\left(\cos x\right)\right)\right) \]
                  11. flip--N/A

                    \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \left(\mathsf{neg}\left(\cos x\right)\right) \cdot \left(\mathsf{neg}\left(\cos x\right)\right)}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)}} \]
                  12. sqr-negN/A

                    \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \color{blue}{\cos x \cdot \cos x}}{\sin x \cdot \sin \varepsilon + \left(\mathsf{neg}\left(\cos x\right)\right)} \]
                  13. sub-negN/A

                    \[\leadsto \cos x \cdot \cos \varepsilon - \frac{\left(\sin x \cdot \sin \varepsilon\right) \cdot \left(\sin x \cdot \sin \varepsilon\right) - \cos x \cdot \cos x}{\color{blue}{\sin x \cdot \sin \varepsilon - \cos x}} \]
                  14. flip-+N/A

                    \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\left(\sin x \cdot \sin \varepsilon + \cos x\right)} \]
                  15. lower-fma.f64N/A

                    \[\leadsto \cos x \cdot \cos \varepsilon - \color{blue}{\mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
                  16. lower-sin.f64N/A

                    \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\color{blue}{\sin x}, \sin \varepsilon, \cos x\right) \]
                  17. lower-sin.f6456.8

                    \[\leadsto \cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \color{blue}{\sin \varepsilon}, \cos x\right) \]
                4. Applied rewrites56.8%

                  \[\leadsto \color{blue}{\cos x \cdot \cos \varepsilon - \mathsf{fma}\left(\sin x, \sin \varepsilon, \cos x\right)} \]
                5. Taylor expanded in eps around 0

                  \[\leadsto \color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)} \]
                6. Step-by-step derivation
                  1. sub-negN/A

                    \[\leadsto \varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) + \left(\mathsf{neg}\left(\sin x\right)\right)\right)} \]
                  2. *-commutativeN/A

                    \[\leadsto \varepsilon \cdot \left(\color{blue}{\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2}} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
                  3. associate-*r*N/A

                    \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right)} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
                  4. *-commutativeN/A

                    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} + \left(\mathsf{neg}\left(\sin x\right)\right)\right) \]
                  5. sin-negN/A

                    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \color{blue}{\sin \left(\mathsf{neg}\left(x\right)\right)}\right) \]
                  6. +-commutativeN/A

                    \[\leadsto \varepsilon \cdot \color{blue}{\left(\sin \left(\mathsf{neg}\left(x\right)\right) + \varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right)} \]
                  7. lower-*.f64N/A

                    \[\leadsto \color{blue}{\varepsilon \cdot \left(\sin \left(\mathsf{neg}\left(x\right)\right) + \varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right)} \]
                  8. +-commutativeN/A

                    \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \sin \left(\mathsf{neg}\left(x\right)\right)\right)} \]
                  9. sin-negN/A

                    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) + \color{blue}{\left(\mathsf{neg}\left(\sin x\right)\right)}\right) \]
                  10. sub-negN/A

                    \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
                  11. lower--.f64N/A

                    \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)} \]
                  12. lower-*.f64N/A

                    \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                  13. lower-*.f64N/A

                    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                  14. lower-cos.f64N/A

                    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \color{blue}{\cos x}\right) - \sin x\right) \]
                  15. lower-sin.f6498.9

                    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \color{blue}{\sin x}\right) \]
                7. Applied rewrites98.9%

                  \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
                8. Taylor expanded in x around 0

                  \[\leadsto \varepsilon \cdot \left(\frac{-1}{2} \cdot \varepsilon + \color{blue}{x \cdot \left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right) - 1\right)}\right) \]
                9. Step-by-step derivation
                  1. Applied rewrites97.2%

                    \[\leadsto \varepsilon \cdot \mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(0.25, \varepsilon \cdot x, -1\right)}, \varepsilon \cdot -0.5\right) \]
                  2. Add Preprocessing

                  Alternative 12: 97.6% accurate, 8.3× speedup?

                  \[\begin{array}{l} \\ \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \varepsilon \cdot 0.16666666666666666, -0.5\right), -x\right) \end{array} \]
                  (FPCore (x eps)
                   :precision binary64
                   (* eps (fma eps (fma x (* eps 0.16666666666666666) -0.5) (- x))))
                  double code(double x, double eps) {
                  	return eps * fma(eps, fma(x, (eps * 0.16666666666666666), -0.5), -x);
                  }
                  
                  function code(x, eps)
                  	return Float64(eps * fma(eps, fma(x, Float64(eps * 0.16666666666666666), -0.5), Float64(-x)))
                  end
                  
                  code[x_, eps_] := N[(eps * N[(eps * N[(x * N[(eps * 0.16666666666666666), $MachinePrecision] + -0.5), $MachinePrecision] + (-x)), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \varepsilon \cdot 0.16666666666666666, -0.5\right), -x\right)
                  \end{array}
                  
                  Derivation
                  1. Initial program 56.6%

                    \[\cos \left(x + \varepsilon\right) - \cos x \]
                  2. Add Preprocessing
                  3. Taylor expanded in eps around 0

                    \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
                  4. Step-by-step derivation
                    1. lower-*.f64N/A

                      \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
                    2. sub-negN/A

                      \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) + \left(\mathsf{neg}\left(\sin x\right)\right)\right)} \]
                    3. lower-fma.f64N/A

                      \[\leadsto \varepsilon \cdot \color{blue}{\mathsf{fma}\left(\varepsilon, \frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right), \mathsf{neg}\left(\sin x\right)\right)} \]
                  5. Applied rewrites99.3%

                    \[\leadsto \color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\cos x, -0.5 + \varepsilon \cdot \left(\varepsilon \cdot 0.041666666666666664\right), \varepsilon \cdot \left(0.16666666666666666 \cdot \sin x\right)\right), \sin \left(-x\right)\right)} \]
                  6. Taylor expanded in x around 0

                    \[\leadsto \varepsilon \cdot \left(x \cdot \left(\frac{1}{6} \cdot {\varepsilon}^{2} - 1\right)\right) + \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{1}{24} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
                  7. Step-by-step derivation
                    1. Applied rewrites97.2%

                      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right)}, \varepsilon \cdot \left(x \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.16666666666666666, -1\right)\right)\right) \]
                    2. Taylor expanded in eps around 0

                      \[\leadsto \varepsilon \cdot \left(-1 \cdot x + \color{blue}{\varepsilon \cdot \left(\frac{1}{6} \cdot \left(\varepsilon \cdot x\right) - \frac{1}{2}\right)}\right) \]
                    3. Step-by-step derivation
                      1. Applied rewrites97.2%

                        \[\leadsto \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \varepsilon \cdot 0.16666666666666666, -0.5\right)}, -x\right) \]
                      2. Add Preprocessing

                      Alternative 13: 97.6% accurate, 14.8× speedup?

                      \[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot -0.5 - x\right) \end{array} \]
                      (FPCore (x eps) :precision binary64 (* eps (- (* eps -0.5) x)))
                      double code(double x, double eps) {
                      	return eps * ((eps * -0.5) - x);
                      }
                      
                      real(8) function code(x, eps)
                          real(8), intent (in) :: x
                          real(8), intent (in) :: eps
                          code = eps * ((eps * (-0.5d0)) - x)
                      end function
                      
                      public static double code(double x, double eps) {
                      	return eps * ((eps * -0.5) - x);
                      }
                      
                      def code(x, eps):
                      	return eps * ((eps * -0.5) - x)
                      
                      function code(x, eps)
                      	return Float64(eps * Float64(Float64(eps * -0.5) - x))
                      end
                      
                      function tmp = code(x, eps)
                      	tmp = eps * ((eps * -0.5) - x);
                      end
                      
                      code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      \varepsilon \cdot \left(\varepsilon \cdot -0.5 - x\right)
                      \end{array}
                      
                      Derivation
                      1. Initial program 56.6%

                        \[\cos \left(x + \varepsilon\right) - \cos x \]
                      2. Add Preprocessing
                      3. Taylor expanded in eps around 0

                        \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
                      4. Step-by-step derivation
                        1. lower-*.f64N/A

                          \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
                        2. sub-negN/A

                          \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) + \left(\mathsf{neg}\left(\sin x\right)\right)\right)} \]
                        3. lower-fma.f64N/A

                          \[\leadsto \varepsilon \cdot \color{blue}{\mathsf{fma}\left(\varepsilon, \frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right), \mathsf{neg}\left(\sin x\right)\right)} \]
                      5. Applied rewrites99.3%

                        \[\leadsto \color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\cos x, -0.5 + \varepsilon \cdot \left(\varepsilon \cdot 0.041666666666666664\right), \varepsilon \cdot \left(0.16666666666666666 \cdot \sin x\right)\right), \sin \left(-x\right)\right)} \]
                      6. Taylor expanded in x around 0

                        \[\leadsto \varepsilon \cdot \left(x \cdot \left(\frac{1}{6} \cdot {\varepsilon}^{2} - 1\right)\right) + \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{1}{24} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
                      7. Step-by-step derivation
                        1. Applied rewrites97.2%

                          \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right)}, \varepsilon \cdot \left(x \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.16666666666666666, -1\right)\right)\right) \]
                        2. Taylor expanded in eps around 0

                          \[\leadsto \varepsilon \cdot \left(-1 \cdot x + \color{blue}{\frac{-1}{2} \cdot \varepsilon}\right) \]
                        3. Step-by-step derivation
                          1. Applied rewrites97.2%

                            \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot -0.5 - \color{blue}{x}\right) \]
                          2. Add Preprocessing

                          Alternative 14: 78.9% accurate, 25.9× speedup?

                          \[\begin{array}{l} \\ -\varepsilon \cdot x \end{array} \]
                          (FPCore (x eps) :precision binary64 (- (* eps x)))
                          double code(double x, double eps) {
                          	return -(eps * x);
                          }
                          
                          real(8) function code(x, eps)
                              real(8), intent (in) :: x
                              real(8), intent (in) :: eps
                              code = -(eps * x)
                          end function
                          
                          public static double code(double x, double eps) {
                          	return -(eps * x);
                          }
                          
                          def code(x, eps):
                          	return -(eps * x)
                          
                          function code(x, eps)
                          	return Float64(-Float64(eps * x))
                          end
                          
                          function tmp = code(x, eps)
                          	tmp = -(eps * x);
                          end
                          
                          code[x_, eps_] := (-N[(eps * x), $MachinePrecision])
                          
                          \begin{array}{l}
                          
                          \\
                          -\varepsilon \cdot x
                          \end{array}
                          
                          Derivation
                          1. Initial program 56.6%

                            \[\cos \left(x + \varepsilon\right) - \cos x \]
                          2. Add Preprocessing
                          3. Taylor expanded in eps around 0

                            \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
                          4. Step-by-step derivation
                            1. lower-*.f64N/A

                              \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) - \sin x\right)} \]
                            2. sub-negN/A

                              \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right)\right) + \left(\mathsf{neg}\left(\sin x\right)\right)\right)} \]
                            3. lower-fma.f64N/A

                              \[\leadsto \varepsilon \cdot \color{blue}{\mathsf{fma}\left(\varepsilon, \frac{-1}{2} \cdot \cos x + \varepsilon \cdot \left(\frac{1}{24} \cdot \left(\varepsilon \cdot \cos x\right) - \frac{-1}{6} \cdot \sin x\right), \mathsf{neg}\left(\sin x\right)\right)} \]
                          5. Applied rewrites99.3%

                            \[\leadsto \color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\cos x, -0.5 + \varepsilon \cdot \left(\varepsilon \cdot 0.041666666666666664\right), \varepsilon \cdot \left(0.16666666666666666 \cdot \sin x\right)\right), \sin \left(-x\right)\right)} \]
                          6. Taylor expanded in x around 0

                            \[\leadsto \varepsilon \cdot \left(x \cdot \left(\frac{1}{6} \cdot {\varepsilon}^{2} - 1\right)\right) + \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{1}{24} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
                          7. Step-by-step derivation
                            1. Applied rewrites97.2%

                              \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.041666666666666664, -0.5\right)}, \varepsilon \cdot \left(x \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.16666666666666666, -1\right)\right)\right) \]
                            2. Taylor expanded in eps around 0

                              \[\leadsto -1 \cdot \left(\varepsilon \cdot \color{blue}{x}\right) \]
                            3. Step-by-step derivation
                              1. Applied rewrites80.8%

                                \[\leadsto x \cdot \left(-\varepsilon\right) \]
                              2. Final simplification80.8%

                                \[\leadsto -\varepsilon \cdot x \]
                              3. Add Preprocessing

                              Alternative 15: 51.5% accurate, 51.8× speedup?

                              \[\begin{array}{l} \\ -1 + 1 \end{array} \]
                              (FPCore (x eps) :precision binary64 (+ -1.0 1.0))
                              double code(double x, double eps) {
                              	return -1.0 + 1.0;
                              }
                              
                              real(8) function code(x, eps)
                                  real(8), intent (in) :: x
                                  real(8), intent (in) :: eps
                                  code = (-1.0d0) + 1.0d0
                              end function
                              
                              public static double code(double x, double eps) {
                              	return -1.0 + 1.0;
                              }
                              
                              def code(x, eps):
                              	return -1.0 + 1.0
                              
                              function code(x, eps)
                              	return Float64(-1.0 + 1.0)
                              end
                              
                              function tmp = code(x, eps)
                              	tmp = -1.0 + 1.0;
                              end
                              
                              code[x_, eps_] := N[(-1.0 + 1.0), $MachinePrecision]
                              
                              \begin{array}{l}
                              
                              \\
                              -1 + 1
                              \end{array}
                              
                              Derivation
                              1. Initial program 56.6%

                                \[\cos \left(x + \varepsilon\right) - \cos x \]
                              2. Add Preprocessing
                              3. Taylor expanded in x around 0

                                \[\leadsto \color{blue}{\cos \varepsilon - 1} \]
                              4. Step-by-step derivation
                                1. sub-negN/A

                                  \[\leadsto \color{blue}{\cos \varepsilon + \left(\mathsf{neg}\left(1\right)\right)} \]
                                2. metadata-evalN/A

                                  \[\leadsto \cos \varepsilon + \color{blue}{-1} \]
                                3. lower-+.f64N/A

                                  \[\leadsto \color{blue}{\cos \varepsilon + -1} \]
                                4. lower-cos.f6454.8

                                  \[\leadsto \color{blue}{\cos \varepsilon} + -1 \]
                              5. Applied rewrites54.8%

                                \[\leadsto \color{blue}{\cos \varepsilon + -1} \]
                              6. Taylor expanded in eps around 0

                                \[\leadsto 1 + -1 \]
                              7. Step-by-step derivation
                                1. Applied rewrites54.6%

                                  \[\leadsto 1 + -1 \]
                                2. Final simplification54.6%

                                  \[\leadsto -1 + 1 \]
                                3. Add Preprocessing

                                Developer Target 1: 99.7% accurate, 0.9× speedup?

                                \[\begin{array}{l} \\ \left(-2 \cdot \sin \left(x + \frac{\varepsilon}{2}\right)\right) \cdot \sin \left(\frac{\varepsilon}{2}\right) \end{array} \]
                                (FPCore (x eps)
                                 :precision binary64
                                 (* (* -2.0 (sin (+ x (/ eps 2.0)))) (sin (/ eps 2.0))))
                                double code(double x, double eps) {
                                	return (-2.0 * sin((x + (eps / 2.0)))) * sin((eps / 2.0));
                                }
                                
                                real(8) function code(x, eps)
                                    real(8), intent (in) :: x
                                    real(8), intent (in) :: eps
                                    code = ((-2.0d0) * sin((x + (eps / 2.0d0)))) * sin((eps / 2.0d0))
                                end function
                                
                                public static double code(double x, double eps) {
                                	return (-2.0 * Math.sin((x + (eps / 2.0)))) * Math.sin((eps / 2.0));
                                }
                                
                                def code(x, eps):
                                	return (-2.0 * math.sin((x + (eps / 2.0)))) * math.sin((eps / 2.0))
                                
                                function code(x, eps)
                                	return Float64(Float64(-2.0 * sin(Float64(x + Float64(eps / 2.0)))) * sin(Float64(eps / 2.0)))
                                end
                                
                                function tmp = code(x, eps)
                                	tmp = (-2.0 * sin((x + (eps / 2.0)))) * sin((eps / 2.0));
                                end
                                
                                code[x_, eps_] := N[(N[(-2.0 * N[Sin[N[(x + N[(eps / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sin[N[(eps / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
                                
                                \begin{array}{l}
                                
                                \\
                                \left(-2 \cdot \sin \left(x + \frac{\varepsilon}{2}\right)\right) \cdot \sin \left(\frac{\varepsilon}{2}\right)
                                \end{array}
                                

                                Developer Target 2: 98.8% accurate, 0.5× speedup?

                                \[\begin{array}{l} \\ {\left(\sqrt[3]{\left(-2 \cdot \sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)}\right)}^{3} \end{array} \]
                                (FPCore (x eps)
                                 :precision binary64
                                 (pow (cbrt (* (* -2.0 (sin (* 0.5 (fma 2.0 x eps)))) (sin (* 0.5 eps)))) 3.0))
                                double code(double x, double eps) {
                                	return pow(cbrt(((-2.0 * sin((0.5 * fma(2.0, x, eps)))) * sin((0.5 * eps)))), 3.0);
                                }
                                
                                function code(x, eps)
                                	return cbrt(Float64(Float64(-2.0 * sin(Float64(0.5 * fma(2.0, x, eps)))) * sin(Float64(0.5 * eps)))) ^ 3.0
                                end
                                
                                code[x_, eps_] := N[Power[N[Power[N[(N[(-2.0 * N[Sin[N[(0.5 * N[(2.0 * x + eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sin[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision], 3.0], $MachinePrecision]
                                
                                \begin{array}{l}
                                
                                \\
                                {\left(\sqrt[3]{\left(-2 \cdot \sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)}\right)}^{3}
                                \end{array}
                                

                                Reproduce

                                ?
                                herbie shell --seed 2024232 
                                (FPCore (x eps)
                                  :name "2cos (problem 3.3.5)"
                                  :precision binary64
                                  :pre (and (and (and (<= -10000.0 x) (<= x 10000.0)) (< (* 1e-16 (fabs x)) eps)) (< eps (fabs x)))
                                
                                  :alt
                                  (! :herbie-platform default (* -2 (sin (+ x (/ eps 2))) (sin (/ eps 2))))
                                
                                  :alt
                                  (! :herbie-platform default (pow (cbrt (* -2 (sin (* 1/2 (fma 2 x eps))) (sin (* 1/2 eps)))) 3))
                                
                                  (- (cos (+ x eps)) (cos x)))