2cos (problem 3.3.5)

Percentage Accurate: 51.5% → 99.8%
Time: 17.4s
Alternatives: 13
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 13 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: 51.5% 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?

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

\\
\begin{array}{l}
t_0 := \sin \left(0.5 \cdot \varepsilon\right)\\
-2 \cdot \left(\mathsf{fma}\left(\cos \left(0.5 \cdot \varepsilon\right), \sin x, \cos x \cdot t\_0\right) \cdot t\_0\right)
\end{array}
\end{array}
Derivation
  1. Initial program 51.1%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  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 rewrites99.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    \[\leadsto \left(\color{blue}{\mathsf{fma}\left(\sin \left(1 \cdot x\right), \cos \left(\varepsilon \cdot 0.5\right), \cos \left(1 \cdot x\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \cdot \sin \left(0.5 \cdot \left(0 + \varepsilon\right)\right)\right) \cdot -2 \]
  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. *-commutativeN/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Alternative 2: 99.6% accurate, 0.5× speedup?

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

\\
\left(\mathsf{fma}\left(\cos \left(0.5 \cdot \varepsilon\right), \sin x, \left(\mathsf{fma}\left(-0.020833333333333332 \cdot \varepsilon, \varepsilon, 0.5\right) \cdot \cos x\right) \cdot \varepsilon\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot -2
\end{array}
Derivation
  1. Initial program 51.1%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  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 rewrites99.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    \[\leadsto \left(\color{blue}{\mathsf{fma}\left(\sin \left(1 \cdot x\right), \cos \left(\varepsilon \cdot 0.5\right), \cos \left(1 \cdot x\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \cdot \sin \left(0.5 \cdot \left(0 + \varepsilon\right)\right)\right) \cdot -2 \]
  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. *-commutativeN/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \left(\mathsf{fma}\left(\cos \left(0.5 \cdot \varepsilon\right), \sin x, \left(\cos x \cdot \mathsf{fma}\left(-0.020833333333333332 \cdot \varepsilon, \varepsilon, 0.5\right)\right) \cdot \varepsilon\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot -2 \]
    2. Final simplification99.7%

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

    Alternative 3: 99.5% accurate, 1.4× speedup?

    \[\begin{array}{l} \\ \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.00026041666666666666, \varepsilon \cdot \varepsilon, -0.020833333333333332\right), \varepsilon \cdot \varepsilon, 0.5\right) \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(2, x, \varepsilon\right) \cdot 0.5\right)\right) \cdot -2 \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (*
      (*
       (*
        (fma
         (fma 0.00026041666666666666 (* eps eps) -0.020833333333333332)
         (* eps eps)
         0.5)
        eps)
       (sin (* (fma 2.0 x eps) 0.5)))
      -2.0))
    double code(double x, double eps) {
    	return ((fma(fma(0.00026041666666666666, (eps * eps), -0.020833333333333332), (eps * eps), 0.5) * eps) * sin((fma(2.0, x, eps) * 0.5))) * -2.0;
    }
    
    function code(x, eps)
    	return Float64(Float64(Float64(fma(fma(0.00026041666666666666, Float64(eps * eps), -0.020833333333333332), Float64(eps * eps), 0.5) * eps) * sin(Float64(fma(2.0, x, eps) * 0.5))) * -2.0)
    end
    
    code[x_, eps_] := N[(N[(N[(N[(N[(0.00026041666666666666 * N[(eps * eps), $MachinePrecision] + -0.020833333333333332), $MachinePrecision] * N[(eps * eps), $MachinePrecision] + 0.5), $MachinePrecision] * eps), $MachinePrecision] * N[Sin[N[(N[(2.0 * x + eps), $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.00026041666666666666, \varepsilon \cdot \varepsilon, -0.020833333333333332\right), \varepsilon \cdot \varepsilon, 0.5\right) \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(2, x, \varepsilon\right) \cdot 0.5\right)\right) \cdot -2
    \end{array}
    
    Derivation
    1. Initial program 51.1%

      \[\cos \left(x + \varepsilon\right) - \cos x \]
    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 rewrites99.7%

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

      \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{1}{2} + {\varepsilon}^{2} \cdot \left(\frac{1}{3840} \cdot {\varepsilon}^{2} - \frac{1}{48}\right)\right)\right)}\right) \cdot -2 \]
    6. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(\left(\frac{1}{2} + {\varepsilon}^{2} \cdot \left(\frac{1}{3840} \cdot {\varepsilon}^{2} - \frac{1}{48}\right)\right) \cdot \varepsilon\right)}\right) \cdot -2 \]
      2. lower-*.f64N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(\left(\frac{1}{2} + {\varepsilon}^{2} \cdot \left(\frac{1}{3840} \cdot {\varepsilon}^{2} - \frac{1}{48}\right)\right) \cdot \varepsilon\right)}\right) \cdot -2 \]
      3. +-commutativeN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{1}{3840} \cdot {\varepsilon}^{2} - \frac{1}{48}\right) + \frac{1}{2}\right)} \cdot \varepsilon\right)\right) \cdot -2 \]
      4. *-commutativeN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\left(\color{blue}{\left(\frac{1}{3840} \cdot {\varepsilon}^{2} - \frac{1}{48}\right) \cdot {\varepsilon}^{2}} + \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      5. lower-fma.f64N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\color{blue}{\mathsf{fma}\left(\frac{1}{3840} \cdot {\varepsilon}^{2} - \frac{1}{48}, {\varepsilon}^{2}, \frac{1}{2}\right)} \cdot \varepsilon\right)\right) \cdot -2 \]
      6. sub-negN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\color{blue}{\frac{1}{3840} \cdot {\varepsilon}^{2} + \left(\mathsf{neg}\left(\frac{1}{48}\right)\right)}, {\varepsilon}^{2}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      7. metadata-evalN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\frac{1}{3840} \cdot {\varepsilon}^{2} + \color{blue}{\frac{-1}{48}}, {\varepsilon}^{2}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      8. lower-fma.f64N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\frac{1}{3840}, {\varepsilon}^{2}, \frac{-1}{48}\right)}, {\varepsilon}^{2}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      9. unpow2N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{3840}, \color{blue}{\varepsilon \cdot \varepsilon}, \frac{-1}{48}\right), {\varepsilon}^{2}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      10. lower-*.f64N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{3840}, \color{blue}{\varepsilon \cdot \varepsilon}, \frac{-1}{48}\right), {\varepsilon}^{2}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      11. unpow2N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{3840}, \varepsilon \cdot \varepsilon, \frac{-1}{48}\right), \color{blue}{\varepsilon \cdot \varepsilon}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      12. lower-*.f6499.7

        \[\leadsto \left(\sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\mathsf{fma}\left(0.00026041666666666666, \varepsilon \cdot \varepsilon, -0.020833333333333332\right), \color{blue}{\varepsilon \cdot \varepsilon}, 0.5\right) \cdot \varepsilon\right)\right) \cdot -2 \]
    7. Applied rewrites99.7%

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

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

    Alternative 4: 99.5% accurate, 1.6× speedup?

    \[\begin{array}{l} \\ \left(\left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.020833333333333332, 0.5\right) \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)\right) \cdot -2 \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (*
      (* (* (fma (* eps eps) -0.020833333333333332 0.5) eps) (sin (fma eps 0.5 x)))
      -2.0))
    double code(double x, double eps) {
    	return ((fma((eps * eps), -0.020833333333333332, 0.5) * eps) * sin(fma(eps, 0.5, x))) * -2.0;
    }
    
    function code(x, eps)
    	return Float64(Float64(Float64(fma(Float64(eps * eps), -0.020833333333333332, 0.5) * eps) * sin(fma(eps, 0.5, x))) * -2.0)
    end
    
    code[x_, eps_] := N[(N[(N[(N[(N[(eps * eps), $MachinePrecision] * -0.020833333333333332 + 0.5), $MachinePrecision] * eps), $MachinePrecision] * N[Sin[N[(eps * 0.5 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.020833333333333332, 0.5\right) \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)\right) \cdot -2
    \end{array}
    
    Derivation
    1. Initial program 51.1%

      \[\cos \left(x + \varepsilon\right) - \cos x \]
    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 rewrites99.7%

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

      \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(\varepsilon \cdot \left(\frac{1}{2} + \frac{-1}{48} \cdot {\varepsilon}^{2}\right)\right)}\right) \cdot -2 \]
    6. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(\left(\frac{1}{2} + \frac{-1}{48} \cdot {\varepsilon}^{2}\right) \cdot \varepsilon\right)}\right) \cdot -2 \]
      2. lower-*.f64N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(\left(\frac{1}{2} + \frac{-1}{48} \cdot {\varepsilon}^{2}\right) \cdot \varepsilon\right)}\right) \cdot -2 \]
      3. +-commutativeN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\color{blue}{\left(\frac{-1}{48} \cdot {\varepsilon}^{2} + \frac{1}{2}\right)} \cdot \varepsilon\right)\right) \cdot -2 \]
      4. *-commutativeN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\left(\color{blue}{{\varepsilon}^{2} \cdot \frac{-1}{48}} + \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      5. lower-fma.f64N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\color{blue}{\mathsf{fma}\left({\varepsilon}^{2}, \frac{-1}{48}, \frac{1}{2}\right)} \cdot \varepsilon\right)\right) \cdot -2 \]
      6. unpow2N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      7. lower-*.f6499.5

        \[\leadsto \left(\sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(\mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, -0.020833333333333332, 0.5\right) \cdot \varepsilon\right)\right) \cdot -2 \]
    7. Applied rewrites99.5%

      \[\leadsto \left(\sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.020833333333333332, 0.5\right) \cdot \varepsilon\right)}\right) \cdot -2 \]
    8. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \left(\sin \color{blue}{\left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right)} \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      2. lift-fma.f64N/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \color{blue}{\left(2 \cdot x + \varepsilon\right)}\right) \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      3. +-commutativeN/A

        \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \color{blue}{\left(\varepsilon + 2 \cdot x\right)}\right) \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      4. distribute-lft-inN/A

        \[\leadsto \left(\sin \color{blue}{\left(\frac{1}{2} \cdot \varepsilon + \frac{1}{2} \cdot \left(2 \cdot x\right)\right)} \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      5. *-commutativeN/A

        \[\leadsto \left(\sin \left(\color{blue}{\varepsilon \cdot \frac{1}{2}} + \frac{1}{2} \cdot \left(2 \cdot x\right)\right) \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      6. associate-*r*N/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + \color{blue}{\left(\frac{1}{2} \cdot 2\right) \cdot x}\right) \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      7. metadata-evalN/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + \color{blue}{1} \cdot x\right) \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      8. *-lft-identityN/A

        \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + \color{blue}{x}\right) \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, \frac{-1}{48}, \frac{1}{2}\right) \cdot \varepsilon\right)\right) \cdot -2 \]
      9. lower-fma.f6499.5

        \[\leadsto \left(\sin \color{blue}{\left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)} \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.020833333333333332, 0.5\right) \cdot \varepsilon\right)\right) \cdot -2 \]
    9. Applied rewrites99.5%

      \[\leadsto \left(\sin \color{blue}{\left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)} \cdot \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.020833333333333332, 0.5\right) \cdot \varepsilon\right)\right) \cdot -2 \]
    10. Final simplification99.5%

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

    Alternative 5: 99.3% accurate, 1.6× speedup?

    \[\begin{array}{l} \\ \left(\left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(2, x, \varepsilon\right) \cdot 0.5\right)\right) \cdot -2 \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (* (* (* 0.5 eps) (sin (* (fma 2.0 x eps) 0.5))) -2.0))
    double code(double x, double eps) {
    	return ((0.5 * eps) * sin((fma(2.0, x, eps) * 0.5))) * -2.0;
    }
    
    function code(x, eps)
    	return Float64(Float64(Float64(0.5 * eps) * sin(Float64(fma(2.0, x, eps) * 0.5))) * -2.0)
    end
    
    code[x_, eps_] := N[(N[(N[(0.5 * eps), $MachinePrecision] * N[Sin[N[(N[(2.0 * x + eps), $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(2, x, \varepsilon\right) \cdot 0.5\right)\right) \cdot -2
    \end{array}
    
    Derivation
    1. Initial program 51.1%

      \[\cos \left(x + \varepsilon\right) - \cos x \]
    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 rewrites99.7%

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

      \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(\frac{1}{2} \cdot \varepsilon\right)}\right) \cdot -2 \]
    6. Step-by-step derivation
      1. lower-*.f6499.0

        \[\leadsto \left(\sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(0.5 \cdot \varepsilon\right)}\right) \cdot -2 \]
    7. Applied rewrites99.0%

      \[\leadsto \left(\sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \color{blue}{\left(0.5 \cdot \varepsilon\right)}\right) \cdot -2 \]
    8. Final simplification99.0%

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

    Alternative 6: 98.9% accurate, 1.7× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.041666666666666664, -0.5\right), \varepsilon, -\sin x\right) \cdot \varepsilon \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (* (fma (fma (* eps eps) 0.041666666666666664 -0.5) eps (- (sin x))) eps))
    double code(double x, double eps) {
    	return fma(fma((eps * eps), 0.041666666666666664, -0.5), eps, -sin(x)) * eps;
    }
    
    function code(x, eps)
    	return Float64(fma(fma(Float64(eps * eps), 0.041666666666666664, -0.5), eps, Float64(-sin(x))) * eps)
    end
    
    code[x_, eps_] := N[(N[(N[(N[(eps * eps), $MachinePrecision] * 0.041666666666666664 + -0.5), $MachinePrecision] * eps + (-N[Sin[x], $MachinePrecision])), $MachinePrecision] * eps), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.041666666666666664, -0.5\right), \varepsilon, -\sin x\right) \cdot \varepsilon
    \end{array}
    
    Derivation
    1. Initial program 51.1%

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

      \[\leadsto \color{blue}{\cos \varepsilon - 1} \]
    4. Step-by-step derivation
      1. lower--.f64N/A

        \[\leadsto \color{blue}{\cos \varepsilon - 1} \]
      2. lower-cos.f6449.5

        \[\leadsto \color{blue}{\cos \varepsilon} - 1 \]
    5. Applied rewrites49.5%

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

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

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

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

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

      Alternative 7: 98.9% accurate, 1.8× speedup?

      \[\begin{array}{l} \\ \left(-0.5 \cdot \varepsilon - \sin x\right) \cdot \varepsilon \end{array} \]
      (FPCore (x eps) :precision binary64 (* (- (* -0.5 eps) (sin x)) eps))
      double code(double x, double eps) {
      	return ((-0.5 * eps) - sin(x)) * eps;
      }
      
      real(8) function code(x, eps)
          real(8), intent (in) :: x
          real(8), intent (in) :: eps
          code = (((-0.5d0) * eps) - sin(x)) * eps
      end function
      
      public static double code(double x, double eps) {
      	return ((-0.5 * eps) - Math.sin(x)) * eps;
      }
      
      def code(x, eps):
      	return ((-0.5 * eps) - math.sin(x)) * eps
      
      function code(x, eps)
      	return Float64(Float64(Float64(-0.5 * eps) - sin(x)) * eps)
      end
      
      function tmp = code(x, eps)
      	tmp = ((-0.5 * eps) - sin(x)) * eps;
      end
      
      code[x_, eps_] := N[(N[(N[(-0.5 * eps), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \left(-0.5 \cdot \varepsilon - \sin x\right) \cdot \varepsilon
      \end{array}
      
      Derivation
      1. Initial program 51.1%

        \[\cos \left(x + \varepsilon\right) - \cos x \]
      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. *-commutativeN/A

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
        12. lower-sin.f6499.1

          \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
      5. Applied rewrites99.1%

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

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

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

        Alternative 8: 98.4% accurate, 4.5× speedup?

        \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot x, 0.16666666666666666, 0.25 \cdot \left(\varepsilon \cdot \varepsilon\right)\right), x, -\varepsilon\right), x, -0.5 \cdot \left(\varepsilon \cdot \varepsilon\right)\right) \end{array} \]
        (FPCore (x eps)
         :precision binary64
         (fma
          (fma (fma (* eps x) 0.16666666666666666 (* 0.25 (* eps eps))) x (- eps))
          x
          (* -0.5 (* eps eps))))
        double code(double x, double eps) {
        	return fma(fma(fma((eps * x), 0.16666666666666666, (0.25 * (eps * eps))), x, -eps), x, (-0.5 * (eps * eps)));
        }
        
        function code(x, eps)
        	return fma(fma(fma(Float64(eps * x), 0.16666666666666666, Float64(0.25 * Float64(eps * eps))), x, Float64(-eps)), x, Float64(-0.5 * Float64(eps * eps)))
        end
        
        code[x_, eps_] := N[(N[(N[(N[(eps * x), $MachinePrecision] * 0.16666666666666666 + N[(0.25 * N[(eps * eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * x + (-eps)), $MachinePrecision] * x + N[(-0.5 * N[(eps * eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot x, 0.16666666666666666, 0.25 \cdot \left(\varepsilon \cdot \varepsilon\right)\right), x, -\varepsilon\right), x, -0.5 \cdot \left(\varepsilon \cdot \varepsilon\right)\right)
        \end{array}
        
        Derivation
        1. Initial program 51.1%

          \[\cos \left(x + \varepsilon\right) - \cos x \]
        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. *-commutativeN/A

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
          12. lower-sin.f6499.1

            \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
        5. Applied rewrites99.1%

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

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

            \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x \cdot x, 0.25, -0.5\right), -x\right) \cdot \varepsilon \]
          2. Taylor expanded in x around 0

            \[\leadsto \frac{-1}{2} \cdot {\varepsilon}^{2} + \color{blue}{x \cdot \left(-1 \cdot \varepsilon + x \cdot \left(\frac{1}{6} \cdot \left(\varepsilon \cdot x\right) + \frac{1}{4} \cdot {\varepsilon}^{2}\right)\right)} \]
          3. Step-by-step derivation
            1. Applied rewrites97.7%

              \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot x, 0.16666666666666666, \left(\varepsilon \cdot \varepsilon\right) \cdot 0.25\right), x, -\varepsilon\right), \color{blue}{x}, \left(\varepsilon \cdot \varepsilon\right) \cdot -0.5\right) \]
            2. Final simplification97.7%

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

            Alternative 9: 98.3% accurate, 6.1× speedup?

            \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.25 \cdot \varepsilon\right), x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon \end{array} \]
            (FPCore (x eps)
             :precision binary64
             (*
              (fma (fma (fma 0.16666666666666666 x (* 0.25 eps)) x -1.0) x (* -0.5 eps))
              eps))
            double code(double x, double eps) {
            	return fma(fma(fma(0.16666666666666666, x, (0.25 * eps)), x, -1.0), x, (-0.5 * eps)) * eps;
            }
            
            function code(x, eps)
            	return Float64(fma(fma(fma(0.16666666666666666, x, Float64(0.25 * eps)), x, -1.0), x, Float64(-0.5 * eps)) * eps)
            end
            
            code[x_, eps_] := N[(N[(N[(N[(0.16666666666666666 * x + N[(0.25 * eps), $MachinePrecision]), $MachinePrecision] * x + -1.0), $MachinePrecision] * x + N[(-0.5 * eps), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.25 \cdot \varepsilon\right), x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon
            \end{array}
            
            Derivation
            1. Initial program 51.1%

              \[\cos \left(x + \varepsilon\right) - \cos x \]
            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. *-commutativeN/A

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

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

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

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

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

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

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

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

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

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

                \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
              12. lower-sin.f6499.1

                \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
            5. Applied rewrites99.1%

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

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

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

              Alternative 10: 97.8% accurate, 8.3× speedup?

              \[\begin{array}{l} \\ \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x \cdot x, 0.25, -0.5\right), -x\right) \cdot \varepsilon \end{array} \]
              (FPCore (x eps)
               :precision binary64
               (* (fma eps (fma (* x x) 0.25 -0.5) (- x)) eps))
              double code(double x, double eps) {
              	return fma(eps, fma((x * x), 0.25, -0.5), -x) * eps;
              }
              
              function code(x, eps)
              	return Float64(fma(eps, fma(Float64(x * x), 0.25, -0.5), Float64(-x)) * eps)
              end
              
              code[x_, eps_] := N[(N[(eps * N[(N[(x * x), $MachinePrecision] * 0.25 + -0.5), $MachinePrecision] + (-x)), $MachinePrecision] * eps), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x \cdot x, 0.25, -0.5\right), -x\right) \cdot \varepsilon
              \end{array}
              
              Derivation
              1. Initial program 51.1%

                \[\cos \left(x + \varepsilon\right) - \cos x \]
              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. *-commutativeN/A

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
                12. lower-sin.f6499.1

                  \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
              5. Applied rewrites99.1%

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

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

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

                Alternative 11: 97.8% accurate, 14.8× speedup?

                \[\begin{array}{l} \\ \mathsf{fma}\left(-0.5, \varepsilon, -x\right) \cdot \varepsilon \end{array} \]
                (FPCore (x eps) :precision binary64 (* (fma -0.5 eps (- x)) eps))
                double code(double x, double eps) {
                	return fma(-0.5, eps, -x) * eps;
                }
                
                function code(x, eps)
                	return Float64(fma(-0.5, eps, Float64(-x)) * eps)
                end
                
                code[x_, eps_] := N[(N[(-0.5 * eps + (-x)), $MachinePrecision] * eps), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \mathsf{fma}\left(-0.5, \varepsilon, -x\right) \cdot \varepsilon
                \end{array}
                
                Derivation
                1. Initial program 51.1%

                  \[\cos \left(x + \varepsilon\right) - \cos x \]
                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. *-commutativeN/A

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
                  12. lower-sin.f6499.1

                    \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
                5. Applied rewrites99.1%

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

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

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

                  Alternative 12: 78.6% accurate, 25.9× speedup?

                  \[\begin{array}{l} \\ x \cdot \left(-\varepsilon\right) \end{array} \]
                  (FPCore (x eps) :precision binary64 (* x (- eps)))
                  double code(double x, double eps) {
                  	return x * -eps;
                  }
                  
                  real(8) function code(x, eps)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: eps
                      code = x * -eps
                  end function
                  
                  public static double code(double x, double eps) {
                  	return x * -eps;
                  }
                  
                  def code(x, eps):
                  	return x * -eps
                  
                  function code(x, eps)
                  	return Float64(x * Float64(-eps))
                  end
                  
                  function tmp = code(x, eps)
                  	tmp = x * -eps;
                  end
                  
                  code[x_, eps_] := N[(x * (-eps)), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  x \cdot \left(-\varepsilon\right)
                  \end{array}
                  
                  Derivation
                  1. Initial program 51.1%

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

                    \[\leadsto \color{blue}{-1 \cdot \left(\varepsilon \cdot \sin x\right)} \]
                  4. Step-by-step derivation
                    1. associate-*r*N/A

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

                      \[\leadsto \color{blue}{\left(-1 \cdot \varepsilon\right) \cdot \sin x} \]
                    3. mul-1-negN/A

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

                      \[\leadsto \color{blue}{\left(-\varepsilon\right)} \cdot \sin x \]
                    5. lower-sin.f6479.0

                      \[\leadsto \left(-\varepsilon\right) \cdot \color{blue}{\sin x} \]
                  5. Applied rewrites79.0%

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

                    \[\leadsto \left(-\varepsilon\right) \cdot x \]
                  7. Step-by-step derivation
                    1. Applied rewrites77.8%

                      \[\leadsto \left(-\varepsilon\right) \cdot x \]
                    2. Final simplification77.8%

                      \[\leadsto x \cdot \left(-\varepsilon\right) \]
                    3. Add Preprocessing

                    Alternative 13: 50.3% 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 51.1%

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

                      \[\leadsto \color{blue}{\cos \varepsilon - 1} \]
                    4. Step-by-step derivation
                      1. lower--.f64N/A

                        \[\leadsto \color{blue}{\cos \varepsilon - 1} \]
                      2. lower-cos.f6449.5

                        \[\leadsto \color{blue}{\cos \varepsilon} - 1 \]
                    5. Applied rewrites49.5%

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

                      \[\leadsto 1 - 1 \]
                    7. Step-by-step derivation
                      1. Applied rewrites49.4%

                        \[\leadsto 1 - 1 \]
                      2. Add Preprocessing

                      Developer Target 1: 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 2024272 
                      (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 (pow (cbrt (* -2 (sin (* 1/2 (fma 2 x eps))) (sin (* 1/2 eps)))) 3))
                      
                        (- (cos (+ x eps)) (cos x)))