2cos (problem 3.3.5)

Percentage Accurate: 53.7% → 99.8%
Time: 18.1s
Alternatives: 15
Speedup: 14.8×

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: 53.7% 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, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(\varepsilon \cdot 0.5\right)\\ \left(t\_0 \cdot \left(t\_0 \cdot \cos x\right) + t\_0 \cdot \left(\cos \left(\varepsilon \cdot 0.5\right) \cdot \sin x\right)\right) \cdot -2 \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (sin (* eps 0.5))))
   (* (+ (* t_0 (* t_0 (cos x))) (* t_0 (* (cos (* eps 0.5)) (sin x)))) -2.0)))
double code(double x, double eps) {
	double t_0 = sin((eps * 0.5));
	return ((t_0 * (t_0 * cos(x))) + (t_0 * (cos((eps * 0.5)) * sin(x)))) * -2.0;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    t_0 = sin((eps * 0.5d0))
    code = ((t_0 * (t_0 * cos(x))) + (t_0 * (cos((eps * 0.5d0)) * sin(x)))) * (-2.0d0)
end function
public static double code(double x, double eps) {
	double t_0 = Math.sin((eps * 0.5));
	return ((t_0 * (t_0 * Math.cos(x))) + (t_0 * (Math.cos((eps * 0.5)) * Math.sin(x)))) * -2.0;
}
def code(x, eps):
	t_0 = math.sin((eps * 0.5))
	return ((t_0 * (t_0 * math.cos(x))) + (t_0 * (math.cos((eps * 0.5)) * math.sin(x)))) * -2.0
function code(x, eps)
	t_0 = sin(Float64(eps * 0.5))
	return Float64(Float64(Float64(t_0 * Float64(t_0 * cos(x))) + Float64(t_0 * Float64(cos(Float64(eps * 0.5)) * sin(x)))) * -2.0)
end
function tmp = code(x, eps)
	t_0 = sin((eps * 0.5));
	tmp = ((t_0 * (t_0 * cos(x))) + (t_0 * (cos((eps * 0.5)) * sin(x)))) * -2.0;
end
code[x_, eps_] := Block[{t$95$0 = N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[(t$95$0 * N[(t$95$0 * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$0 * N[(N[Cos[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[Sin[x], $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 \left(t\_0 \cdot \cos x\right) + t\_0 \cdot \left(\cos \left(\varepsilon \cdot 0.5\right) \cdot \sin x\right)\right) \cdot -2
\end{array}
\end{array}
Derivation
  1. Initial program 48.7%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  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-rgt-inN/A

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

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

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

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

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

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

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

    \[\leadsto \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)\right)} \cdot -2 \]
  8. Step-by-step derivation
    1. Applied rewrites99.8%

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

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

    Alternative 2: 99.8% accurate, 0.4× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(\varepsilon \cdot 0.5\right)\\ -2 \cdot \left(t\_0 \cdot \mathsf{fma}\left(\sin x, \cos \left(\varepsilon \cdot 0.5\right), t\_0 \cdot \cos x\right)\right) \end{array} \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (let* ((t_0 (sin (* eps 0.5))))
       (* -2.0 (* t_0 (fma (sin x) (cos (* eps 0.5)) (* t_0 (cos x)))))))
    double code(double x, double eps) {
    	double t_0 = sin((eps * 0.5));
    	return -2.0 * (t_0 * fma(sin(x), cos((eps * 0.5)), (t_0 * cos(x))));
    }
    
    function code(x, eps)
    	t_0 = sin(Float64(eps * 0.5))
    	return Float64(-2.0 * Float64(t_0 * fma(sin(x), cos(Float64(eps * 0.5)), Float64(t_0 * cos(x)))))
    end
    
    code[x_, eps_] := Block[{t$95$0 = N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(-2.0 * N[(t$95$0 * N[(N[Sin[x], $MachinePrecision] * N[Cos[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] + N[(t$95$0 * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := \sin \left(\varepsilon \cdot 0.5\right)\\
    -2 \cdot \left(t\_0 \cdot \mathsf{fma}\left(\sin x, \cos \left(\varepsilon \cdot 0.5\right), t\_0 \cdot \cos x\right)\right)
    \end{array}
    \end{array}
    
    Derivation
    1. Initial program 48.7%

      \[\cos \left(x + \varepsilon\right) - \cos x \]
    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-rgt-inN/A

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)\right)} \cdot -2 \]
    8. Step-by-step derivation
      1. Applied rewrites99.7%

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

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

      Alternative 3: 99.5% accurate, 0.5× speedup?

      \[\begin{array}{l} \\ -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos \left(\varepsilon \cdot 0.5\right) \cdot \sin x\right) + \varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -0.020833333333333332, 0.25\right)\right)\right)\right) \end{array} \]
      (FPCore (x eps)
       :precision binary64
       (*
        -2.0
        (+
         (* (sin (* eps 0.5)) (* (cos (* eps 0.5)) (sin x)))
         (* eps (* eps (* (cos x) (fma eps (* eps -0.020833333333333332) 0.25)))))))
      double code(double x, double eps) {
      	return -2.0 * ((sin((eps * 0.5)) * (cos((eps * 0.5)) * sin(x))) + (eps * (eps * (cos(x) * fma(eps, (eps * -0.020833333333333332), 0.25)))));
      }
      
      function code(x, eps)
      	return Float64(-2.0 * Float64(Float64(sin(Float64(eps * 0.5)) * Float64(cos(Float64(eps * 0.5)) * sin(x))) + Float64(eps * Float64(eps * Float64(cos(x) * fma(eps, Float64(eps * -0.020833333333333332), 0.25))))))
      end
      
      code[x_, eps_] := N[(-2.0 * N[(N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[(N[Cos[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(eps * N[(eps * N[(N[Cos[x], $MachinePrecision] * N[(eps * N[(eps * -0.020833333333333332), $MachinePrecision] + 0.25), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos \left(\varepsilon \cdot 0.5\right) \cdot \sin x\right) + \varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -0.020833333333333332, 0.25\right)\right)\right)\right)
      \end{array}
      
      Derivation
      1. Initial program 48.7%

        \[\cos \left(x + \varepsilon\right) - \cos x \]
      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-rgt-inN/A

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)\right)} \cdot -2 \]
      8. Step-by-step derivation
        1. Applied rewrites99.8%

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

          \[\leadsto \left({\varepsilon}^{2} \cdot \left(\frac{-1}{48} \cdot \left({\varepsilon}^{2} \cdot \cos x\right) + \frac{1}{4} \cdot \cos x\right) + \color{blue}{\left(\cos \left(\varepsilon \cdot \frac{1}{2}\right) \cdot \sin x\right)} \cdot \sin \left(\varepsilon \cdot \frac{1}{2}\right)\right) \cdot -2 \]
        3. Step-by-step derivation
          1. Applied rewrites99.5%

            \[\leadsto \left(\varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -0.020833333333333332, 0.25\right)\right)\right) + \color{blue}{\left(\cos \left(\varepsilon \cdot 0.5\right) \cdot \sin x\right)} \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \cdot -2 \]
          2. Final simplification99.5%

            \[\leadsto -2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos \left(\varepsilon \cdot 0.5\right) \cdot \sin x\right) + \varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -0.020833333333333332, 0.25\right)\right)\right)\right) \]
          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 48.7%

            \[\cos \left(x + \varepsilon\right) - \cos x \]
          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-rgt-inN/A

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

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

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

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

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

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

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

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

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

          Alternative 5: 99.6% accurate, 1.3× speedup?

          \[\begin{array}{l} \\ -2 \cdot \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right) \cdot \sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)\right) \end{array} \]
          (FPCore (x eps)
           :precision binary64
           (*
            -2.0
            (*
             (*
              eps
              (fma
               (* eps eps)
               (fma
                eps
                (* eps (fma eps (* eps -1.5500992063492063e-6) 0.00026041666666666666))
                -0.020833333333333332)
               0.5))
             (sin (fma eps 0.5 x)))))
          double code(double x, double eps) {
          	return -2.0 * ((eps * fma((eps * eps), fma(eps, (eps * fma(eps, (eps * -1.5500992063492063e-6), 0.00026041666666666666)), -0.020833333333333332), 0.5)) * sin(fma(eps, 0.5, x)));
          }
          
          function code(x, eps)
          	return Float64(-2.0 * Float64(Float64(eps * fma(Float64(eps * eps), fma(eps, Float64(eps * fma(eps, Float64(eps * -1.5500992063492063e-6), 0.00026041666666666666)), -0.020833333333333332), 0.5)) * sin(fma(eps, 0.5, x))))
          end
          
          code[x_, eps_] := N[(-2.0 * N[(N[(eps * N[(N[(eps * eps), $MachinePrecision] * N[(eps * N[(eps * N[(eps * N[(eps * -1.5500992063492063e-6), $MachinePrecision] + 0.00026041666666666666), $MachinePrecision]), $MachinePrecision] + -0.020833333333333332), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision] * N[Sin[N[(eps * 0.5 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          -2 \cdot \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right) \cdot \sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)\right)
          \end{array}
          
          Derivation
          1. Initial program 48.7%

            \[\cos \left(x + \varepsilon\right) - \cos x \]
          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 0

            \[\leadsto \left(\color{blue}{\left(\varepsilon \cdot \left(\frac{1}{2} + {\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) - \frac{1}{48}\right)\right)\right)} \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
          6. Step-by-step derivation
            1. lower-*.f64N/A

              \[\leadsto \left(\color{blue}{\left(\varepsilon \cdot \left(\frac{1}{2} + {\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) - \frac{1}{48}\right)\right)\right)} \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            2. +-commutativeN/A

              \[\leadsto \left(\left(\varepsilon \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) - \frac{1}{48}\right) + \frac{1}{2}\right)}\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            3. lower-fma.f64N/A

              \[\leadsto \left(\left(\varepsilon \cdot \color{blue}{\mathsf{fma}\left({\varepsilon}^{2}, {\varepsilon}^{2} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) - \frac{1}{48}, \frac{1}{2}\right)}\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            4. unpow2N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, {\varepsilon}^{2} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) - \frac{1}{48}, \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            5. lower-*.f64N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, {\varepsilon}^{2} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) - \frac{1}{48}, \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            6. sub-negN/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) + \left(\mathsf{neg}\left(\frac{1}{48}\right)\right)}, \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            7. unpow2N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right) + \left(\mathsf{neg}\left(\frac{1}{48}\right)\right), \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            8. associate-*l*N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right)\right)} + \left(\mathsf{neg}\left(\frac{1}{48}\right)\right), \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            9. metadata-evalN/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \varepsilon \cdot \left(\varepsilon \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right)\right) + \color{blue}{\frac{-1}{48}}, \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            10. lower-fma.f64N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \color{blue}{\mathsf{fma}\left(\varepsilon, \varepsilon \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right), \frac{-1}{48}\right)}, \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            11. lower-*.f64N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot \left(\frac{1}{3840} + \frac{-1}{645120} \cdot {\varepsilon}^{2}\right)}, \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            12. +-commutativeN/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \color{blue}{\left(\frac{-1}{645120} \cdot {\varepsilon}^{2} + \frac{1}{3840}\right)}, \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            13. *-commutativeN/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \left(\color{blue}{{\varepsilon}^{2} \cdot \frac{-1}{645120}} + \frac{1}{3840}\right), \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            14. unpow2N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \left(\color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot \frac{-1}{645120} + \frac{1}{3840}\right), \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            15. associate-*l*N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \frac{-1}{645120}\right)} + \frac{1}{3840}\right), \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            16. lower-fma.f64N/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \color{blue}{\mathsf{fma}\left(\varepsilon, \varepsilon \cdot \frac{-1}{645120}, \frac{1}{3840}\right)}, \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \frac{1}{2}\right)\right) \cdot -2 \]
            17. lower-*.f6499.3

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot -1.5500992063492063 \cdot 10^{-6}}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right) \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \cdot -2 \]
          7. Applied rewrites99.3%

            \[\leadsto \left(\color{blue}{\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right)} \cdot \sin \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \cdot -2 \]
          8. Taylor expanded in eps around 0

            \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \frac{-1}{645120}, \frac{1}{3840}\right), \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \color{blue}{\left(x + \frac{1}{2} \cdot \varepsilon\right)}\right) \cdot -2 \]
          9. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \frac{-1}{645120}, \frac{1}{3840}\right), \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \color{blue}{\left(\frac{1}{2} \cdot \varepsilon + x\right)}\right) \cdot -2 \]
            2. *-commutativeN/A

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \frac{-1}{645120}, \frac{1}{3840}\right), \frac{-1}{48}\right), \frac{1}{2}\right)\right) \cdot \sin \left(\color{blue}{\varepsilon \cdot \frac{1}{2}} + x\right)\right) \cdot -2 \]
            3. lower-fma.f6499.3

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right) \cdot \sin \color{blue}{\left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)}\right) \cdot -2 \]
          10. Applied rewrites99.3%

            \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -1.5500992063492063 \cdot 10^{-6}, 0.00026041666666666666\right), -0.020833333333333332\right), 0.5\right)\right) \cdot \sin \color{blue}{\left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)}\right) \cdot -2 \]
          11. Final simplification99.3%

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

          Alternative 6: 99.5% accurate, 1.4× speedup?

          \[\begin{array}{l} \\ -2 \cdot \left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.00026041666666666666, -0.020833333333333332\right), 0.5\right)\right)\right) \end{array} \]
          (FPCore (x eps)
           :precision binary64
           (*
            -2.0
            (*
             (sin (fma 0.5 eps x))
             (*
              eps
              (fma
               (* eps eps)
               (fma eps (* eps 0.00026041666666666666) -0.020833333333333332)
               0.5)))))
          double code(double x, double eps) {
          	return -2.0 * (sin(fma(0.5, eps, x)) * (eps * fma((eps * eps), fma(eps, (eps * 0.00026041666666666666), -0.020833333333333332), 0.5)));
          }
          
          function code(x, eps)
          	return Float64(-2.0 * Float64(sin(fma(0.5, eps, x)) * Float64(eps * fma(Float64(eps * eps), fma(eps, Float64(eps * 0.00026041666666666666), -0.020833333333333332), 0.5))))
          end
          
          code[x_, eps_] := N[(-2.0 * N[(N[Sin[N[(0.5 * eps + x), $MachinePrecision]], $MachinePrecision] * N[(eps * N[(N[(eps * eps), $MachinePrecision] * N[(eps * N[(eps * 0.00026041666666666666), $MachinePrecision] + -0.020833333333333332), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          -2 \cdot \left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.00026041666666666666, -0.020833333333333332\right), 0.5\right)\right)\right)
          \end{array}
          
          Derivation
          1. Initial program 48.7%

            \[\cos \left(x + \varepsilon\right) - \cos x \]
          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-rgt-inN/A

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

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

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

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

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

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

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

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

            \[\leadsto \left(\left(\varepsilon \cdot \left(\frac{1}{2} + {\varepsilon}^{2} \cdot \left(\frac{1}{3840} \cdot {\varepsilon}^{2} - \frac{1}{48}\right)\right)\right) \cdot \sin \color{blue}{\left(\mathsf{fma}\left(\frac{1}{2}, \varepsilon, x\right)\right)}\right) \cdot -2 \]
          9. Step-by-step derivation
            1. Applied rewrites99.3%

              \[\leadsto \left(\left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.00026041666666666666, -0.020833333333333332\right), 0.5\right)\right) \cdot \sin \color{blue}{\left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)}\right) \cdot -2 \]
            2. Final simplification99.3%

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

            Alternative 7: 99.5% accurate, 1.6× speedup?

            \[\begin{array}{l} \\ -2 \cdot \left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -0.020833333333333332, 0.5\right)\right)\right) \end{array} \]
            (FPCore (x eps)
             :precision binary64
             (*
              -2.0
              (*
               (sin (fma 0.5 eps x))
               (* eps (fma eps (* eps -0.020833333333333332) 0.5)))))
            double code(double x, double eps) {
            	return -2.0 * (sin(fma(0.5, eps, x)) * (eps * fma(eps, (eps * -0.020833333333333332), 0.5)));
            }
            
            function code(x, eps)
            	return Float64(-2.0 * Float64(sin(fma(0.5, eps, x)) * Float64(eps * fma(eps, Float64(eps * -0.020833333333333332), 0.5))))
            end
            
            code[x_, eps_] := N[(-2.0 * N[(N[Sin[N[(0.5 * eps + x), $MachinePrecision]], $MachinePrecision] * N[(eps * N[(eps * N[(eps * -0.020833333333333332), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            -2 \cdot \left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \left(\varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -0.020833333333333332, 0.5\right)\right)\right)
            \end{array}
            
            Derivation
            1. Initial program 48.7%

              \[\cos \left(x + \varepsilon\right) - \cos x \]
            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-rgt-inN/A

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

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

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

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

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

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

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

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

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

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

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

              Alternative 8: 99.2% accurate, 1.7× speedup?

              \[\begin{array}{l} \\ -2 \cdot \left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \left(\varepsilon \cdot 0.5\right)\right) \end{array} \]
              (FPCore (x eps)
               :precision binary64
               (* -2.0 (* (sin (fma 0.5 eps x)) (* eps 0.5))))
              double code(double x, double eps) {
              	return -2.0 * (sin(fma(0.5, eps, x)) * (eps * 0.5));
              }
              
              function code(x, eps)
              	return Float64(-2.0 * Float64(sin(fma(0.5, eps, x)) * Float64(eps * 0.5)))
              end
              
              code[x_, eps_] := N[(-2.0 * N[(N[Sin[N[(0.5 * eps + x), $MachinePrecision]], $MachinePrecision] * N[(eps * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              -2 \cdot \left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \left(\varepsilon \cdot 0.5\right)\right)
              \end{array}
              
              Derivation
              1. Initial program 48.7%

                \[\cos \left(x + \varepsilon\right) - \cos x \]
              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-rgt-inN/A

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

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

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

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

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

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

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

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

                \[\leadsto \left(\left(\frac{1}{2} \cdot \varepsilon\right) \cdot \sin \color{blue}{\left(\mathsf{fma}\left(\frac{1}{2}, \varepsilon, x\right)\right)}\right) \cdot -2 \]
              9. Step-by-step derivation
                1. Applied rewrites98.7%

                  \[\leadsto \left(\left(\varepsilon \cdot 0.5\right) \cdot \sin \color{blue}{\left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)}\right) \cdot -2 \]
                2. Final simplification98.7%

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

                Alternative 9: 98.8% 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 48.7%

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

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

                    \[\leadsto \color{blue}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}} \]
                  3. clear-numN/A

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

                    \[\leadsto \color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) + \cos x}{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}}} \]
                  5. clear-numN/A

                    \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}}}} \]
                  6. flip--N/A

                    \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                  7. lift--.f64N/A

                    \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                  8. lower-/.f6448.7

                    \[\leadsto \frac{1}{\color{blue}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                4. Applied rewrites48.7%

                  \[\leadsto \color{blue}{\frac{1}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                  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.f6498.7

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

                  \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
                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 rewrites98.2%

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

                  Alternative 10: 98.4% accurate, 4.5× speedup?

                  \[\begin{array}{l} \\ \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.25, \varepsilon \cdot \left(x \cdot 0.16666666666666666\right)\right), -\varepsilon\right), \varepsilon \cdot \left(\varepsilon \cdot -0.5\right)\right) \end{array} \]
                  (FPCore (x eps)
                   :precision binary64
                   (fma
                    x
                    (fma x (fma eps (* eps 0.25) (* eps (* x 0.16666666666666666))) (- eps))
                    (* eps (* eps -0.5))))
                  double code(double x, double eps) {
                  	return fma(x, fma(x, fma(eps, (eps * 0.25), (eps * (x * 0.16666666666666666))), -eps), (eps * (eps * -0.5)));
                  }
                  
                  function code(x, eps)
                  	return fma(x, fma(x, fma(eps, Float64(eps * 0.25), Float64(eps * Float64(x * 0.16666666666666666))), Float64(-eps)), Float64(eps * Float64(eps * -0.5)))
                  end
                  
                  code[x_, eps_] := N[(x * N[(x * N[(eps * N[(eps * 0.25), $MachinePrecision] + N[(eps * N[(x * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + (-eps)), $MachinePrecision] + N[(eps * N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.25, \varepsilon \cdot \left(x \cdot 0.16666666666666666\right)\right), -\varepsilon\right), \varepsilon \cdot \left(\varepsilon \cdot -0.5\right)\right)
                  \end{array}
                  
                  Derivation
                  1. Initial program 48.7%

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

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

                      \[\leadsto \color{blue}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}} \]
                    3. clear-numN/A

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

                      \[\leadsto \color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) + \cos x}{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}}} \]
                    5. clear-numN/A

                      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}}}} \]
                    6. flip--N/A

                      \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                    7. lift--.f64N/A

                      \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                    8. lower-/.f6448.7

                      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                  4. Applied rewrites48.7%

                    \[\leadsto \color{blue}{\frac{1}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                  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

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

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

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

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

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

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

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

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

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

                      \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                    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.f6498.7

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

                    \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
                  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 rewrites97.1%

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

                    Alternative 11: 98.2% 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 48.7%

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

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

                        \[\leadsto \color{blue}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}} \]
                      3. clear-numN/A

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

                        \[\leadsto \color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) + \cos x}{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}}} \]
                      5. clear-numN/A

                        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}}}} \]
                      6. flip--N/A

                        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                      7. lift--.f64N/A

                        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                      8. lower-/.f6448.7

                        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                    4. Applied rewrites48.7%

                      \[\leadsto \color{blue}{\frac{1}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                    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

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

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

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

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

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

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

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

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

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

                        \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                      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.f6498.7

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

                      \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
                    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 rewrites96.9%

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

                      Alternative 12: 97.7% accurate, 10.9× speedup?

                      \[\begin{array}{l} \\ \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -0.5, -\varepsilon \cdot x\right) \end{array} \]
                      (FPCore (x eps) :precision binary64 (fma eps (* eps -0.5) (- (* eps x))))
                      double code(double x, double eps) {
                      	return fma(eps, (eps * -0.5), -(eps * x));
                      }
                      
                      function code(x, eps)
                      	return fma(eps, Float64(eps * -0.5), Float64(-Float64(eps * x)))
                      end
                      
                      code[x_, eps_] := N[(eps * N[(eps * -0.5), $MachinePrecision] + (-N[(eps * x), $MachinePrecision])), $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      \mathsf{fma}\left(\varepsilon, \varepsilon \cdot -0.5, -\varepsilon \cdot x\right)
                      \end{array}
                      
                      Derivation
                      1. Initial program 48.7%

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

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

                          \[\leadsto \color{blue}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}} \]
                        3. clear-numN/A

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

                          \[\leadsto \color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) + \cos x}{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}}} \]
                        5. clear-numN/A

                          \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}}}} \]
                        6. flip--N/A

                          \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                        7. lift--.f64N/A

                          \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                        8. lower-/.f6448.7

                          \[\leadsto \frac{1}{\color{blue}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                      4. Applied rewrites48.7%

                        \[\leadsto \color{blue}{\frac{1}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                      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

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

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

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

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

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

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

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

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

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

                          \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                        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.f6498.7

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

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

                        \[\leadsto -1 \cdot \left(\varepsilon \cdot x\right) + \color{blue}{\frac{-1}{2} \cdot {\varepsilon}^{2}} \]
                      9. Step-by-step derivation
                        1. Applied rewrites96.3%

                          \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot -0.5}, \varepsilon \cdot \left(-x\right)\right) \]
                        2. Final simplification96.3%

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

                        Alternative 13: 97.7% 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 48.7%

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

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

                            \[\leadsto \color{blue}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}} \]
                          3. clear-numN/A

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

                            \[\leadsto \color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) + \cos x}{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}}} \]
                          5. clear-numN/A

                            \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\cos \left(x + \varepsilon\right) \cdot \cos \left(x + \varepsilon\right) - \cos x \cdot \cos x}{\cos \left(x + \varepsilon\right) + \cos x}}}} \]
                          6. flip--N/A

                            \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                          7. lift--.f64N/A

                            \[\leadsto \frac{1}{\frac{1}{\color{blue}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                          8. lower-/.f6448.7

                            \[\leadsto \frac{1}{\color{blue}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                        4. Applied rewrites48.7%

                          \[\leadsto \color{blue}{\frac{1}{\frac{1}{\cos \left(x + \varepsilon\right) - \cos x}}} \]
                        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

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

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

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

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

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

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

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

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

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

                            \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \]
                          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.f6498.7

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

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

                          \[\leadsto \varepsilon \cdot \left(-1 \cdot x + \color{blue}{\frac{-1}{2} \cdot \varepsilon}\right) \]
                        9. Step-by-step derivation
                          1. Applied rewrites96.3%

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

                          Alternative 14: 53.6% accurate, 18.8× speedup?

                          \[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot -0.5\right) \end{array} \]
                          (FPCore (x eps) :precision binary64 (* eps (* eps -0.5)))
                          double code(double x, double eps) {
                          	return eps * (eps * -0.5);
                          }
                          
                          real(8) function code(x, eps)
                              real(8), intent (in) :: x
                              real(8), intent (in) :: eps
                              code = eps * (eps * (-0.5d0))
                          end function
                          
                          public static double code(double x, double eps) {
                          	return eps * (eps * -0.5);
                          }
                          
                          def code(x, eps):
                          	return eps * (eps * -0.5)
                          
                          function code(x, eps)
                          	return Float64(eps * Float64(eps * -0.5))
                          end
                          
                          function tmp = code(x, eps)
                          	tmp = eps * (eps * -0.5);
                          end
                          
                          code[x_, eps_] := N[(eps * N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]
                          
                          \begin{array}{l}
                          
                          \\
                          \varepsilon \cdot \left(\varepsilon \cdot -0.5\right)
                          \end{array}
                          
                          Derivation
                          1. Initial program 48.7%

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

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

                              \[\leadsto \color{blue}{-1 + \cos \varepsilon} \]
                            5. lower-cos.f6447.1

                              \[\leadsto -1 + \color{blue}{\cos \varepsilon} \]
                          5. Applied rewrites47.1%

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

                            \[\leadsto \frac{-1}{2} \cdot \color{blue}{{\varepsilon}^{2}} \]
                          7. Step-by-step derivation
                            1. Applied rewrites48.7%

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

                            Alternative 15: 52.3% 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 48.7%

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

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

                                \[\leadsto \color{blue}{-1 + \cos \varepsilon} \]
                              5. lower-cos.f6447.1

                                \[\leadsto -1 + \color{blue}{\cos \varepsilon} \]
                            5. Applied rewrites47.1%

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

                              \[\leadsto -1 + 1 \]
                            7. Step-by-step derivation
                              1. Applied rewrites46.9%

                                \[\leadsto -1 + 1 \]
                              2. 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 2024228 
                              (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)))