Asymptote A

Percentage Accurate: 77.2% → 99.9%
Time: 7.2s
Alternatives: 6
Speedup: 1.2×

Specification

?
\[\begin{array}{l} \\ \frac{1}{x + 1} - \frac{1}{x - 1} \end{array} \]
(FPCore (x) :precision binary64 (- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))
double code(double x) {
	return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (1.0d0 / (x + 1.0d0)) - (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
	return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0));
}
def code(x):
	return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0))
function code(x)
	return Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(1.0 / Float64(x - 1.0)))
end
function tmp = code(x)
	tmp = (1.0 / (x + 1.0)) - (1.0 / (x - 1.0));
end
code[x_] := N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{x + 1} - \frac{1}{x - 1}
\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 6 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: 77.2% accurate, 1.0× speedup?

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

\\
\frac{1}{x + 1} - \frac{1}{x - 1}
\end{array}

Alternative 1: 99.9% accurate, 1.2× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ \frac{\frac{-2}{1 - x\_m}}{-1 - x\_m} \end{array} \]
x_m = (fabs.f64 x)
(FPCore (x_m) :precision binary64 (/ (/ -2.0 (- 1.0 x_m)) (- -1.0 x_m)))
x_m = fabs(x);
double code(double x_m) {
	return (-2.0 / (1.0 - x_m)) / (-1.0 - x_m);
}
x_m = abs(x)
real(8) function code(x_m)
    real(8), intent (in) :: x_m
    code = ((-2.0d0) / (1.0d0 - x_m)) / ((-1.0d0) - x_m)
end function
x_m = Math.abs(x);
public static double code(double x_m) {
	return (-2.0 / (1.0 - x_m)) / (-1.0 - x_m);
}
x_m = math.fabs(x)
def code(x_m):
	return (-2.0 / (1.0 - x_m)) / (-1.0 - x_m)
x_m = abs(x)
function code(x_m)
	return Float64(Float64(-2.0 / Float64(1.0 - x_m)) / Float64(-1.0 - x_m))
end
x_m = abs(x);
function tmp = code(x_m)
	tmp = (-2.0 / (1.0 - x_m)) / (-1.0 - x_m);
end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := N[(N[(-2.0 / N[(1.0 - x$95$m), $MachinePrecision]), $MachinePrecision] / N[(-1.0 - x$95$m), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|

\\
\frac{\frac{-2}{1 - x\_m}}{-1 - x\_m}
\end{array}
Derivation
  1. Initial program 76.8%

    \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
    2. +-commutative76.8%

      \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
    3. distribute-neg-frac276.8%

      \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
    4. neg-sub076.8%

      \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
    5. associate-+l-76.8%

      \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
    6. neg-sub076.8%

      \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
    7. remove-double-neg76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
    8. distribute-neg-in76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
    9. sub-neg76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
    10. distribute-neg-frac276.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
    11. sub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
    12. +-commutative76.8%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
    13. unsub-neg76.8%

      \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
    14. sub-neg76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
    15. +-commutative76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
    16. unsub-neg76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
    17. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
  3. Simplified76.8%

    \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. sub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{1 - x} + \left(-\frac{1}{-1 - x}\right)} \]
    2. distribute-neg-frac76.8%

      \[\leadsto \frac{1}{1 - x} + \color{blue}{\frac{-1}{-1 - x}} \]
    3. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} + \frac{\color{blue}{-1}}{-1 - x} \]
  6. Applied egg-rr76.8%

    \[\leadsto \color{blue}{\frac{1}{1 - x} + \frac{-1}{-1 - x}} \]
  7. Step-by-step derivation
    1. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} + \frac{\color{blue}{-1}}{-1 - x} \]
    2. distribute-neg-frac76.8%

      \[\leadsto \frac{1}{1 - x} + \color{blue}{\left(-\frac{1}{-1 - x}\right)} \]
    3. unsub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. *-rgt-identity76.8%

      \[\leadsto \color{blue}{\frac{1}{1 - x} \cdot 1} - \frac{1}{-1 - x} \]
    5. *-inverses76.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \frac{\color{blue}{\frac{-\left(1 - x\right)}{-\left(1 - x\right)}}}{-1 - x} \]
    6. associate-/r*54.1%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \color{blue}{\frac{-\left(1 - x\right)}{\left(-\left(1 - x\right)\right) \cdot \left(-1 - x\right)}} \]
    7. neg-mul-154.1%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \frac{\color{blue}{-1 \cdot \left(1 - x\right)}}{\left(-\left(1 - x\right)\right) \cdot \left(-1 - x\right)} \]
    8. times-frac76.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \color{blue}{\frac{-1}{-\left(1 - x\right)} \cdot \frac{1 - x}{-1 - x}} \]
    9. distribute-frac-neg276.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \color{blue}{\left(-\frac{-1}{1 - x}\right)} \cdot \frac{1 - x}{-1 - x} \]
    10. distribute-neg-frac76.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \color{blue}{\frac{--1}{1 - x}} \cdot \frac{1 - x}{-1 - x} \]
    11. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \frac{\color{blue}{1}}{1 - x} \cdot \frac{1 - x}{-1 - x} \]
    12. distribute-lft-out--76.8%

      \[\leadsto \color{blue}{\frac{1}{1 - x} \cdot \left(1 - \frac{1 - x}{-1 - x}\right)} \]
    13. *-inverses76.8%

      \[\leadsto \frac{1}{1 - x} \cdot \left(\color{blue}{\frac{-1 - x}{-1 - x}} - \frac{1 - x}{-1 - x}\right) \]
    14. div-sub77.4%

      \[\leadsto \frac{1}{1 - x} \cdot \color{blue}{\frac{\left(-1 - x\right) - \left(1 - x\right)}{-1 - x}} \]
    15. associate--r+80.6%

      \[\leadsto \frac{1}{1 - x} \cdot \frac{\color{blue}{-1 - \left(x + \left(1 - x\right)\right)}}{-1 - x} \]
    16. associate-*r/80.6%

      \[\leadsto \color{blue}{\frac{\frac{1}{1 - x} \cdot \left(-1 - \left(x + \left(1 - x\right)\right)\right)}{-1 - x}} \]
    17. associate-*l/80.6%

      \[\leadsto \color{blue}{\frac{\frac{1}{1 - x}}{-1 - x} \cdot \left(-1 - \left(x + \left(1 - x\right)\right)\right)} \]
  8. Simplified99.2%

    \[\leadsto \color{blue}{\frac{-2}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
  9. Step-by-step derivation
    1. associate-/r*99.9%

      \[\leadsto \color{blue}{\frac{\frac{-2}{1 - x}}{-1 - x}} \]
    2. div-inv99.8%

      \[\leadsto \color{blue}{\frac{-2}{1 - x} \cdot \frac{1}{-1 - x}} \]
  10. Applied egg-rr99.8%

    \[\leadsto \color{blue}{\frac{-2}{1 - x} \cdot \frac{1}{-1 - x}} \]
  11. Applied egg-rr99.9%

    \[\leadsto \color{blue}{\frac{\frac{-2}{1 - x}}{-1 - x}} \]
  12. Final simplification99.9%

    \[\leadsto \frac{\frac{-2}{1 - x}}{-1 - x} \]
  13. Add Preprocessing

Alternative 2: 98.0% accurate, 0.9× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ \begin{array}{l} \mathbf{if}\;x\_m \leq 0.75:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;\frac{2}{x\_m \cdot \left(1 - x\_m\right)}\\ \end{array} \end{array} \]
x_m = (fabs.f64 x)
(FPCore (x_m)
 :precision binary64
 (if (<= x_m 0.75) 2.0 (/ 2.0 (* x_m (- 1.0 x_m)))))
x_m = fabs(x);
double code(double x_m) {
	double tmp;
	if (x_m <= 0.75) {
		tmp = 2.0;
	} else {
		tmp = 2.0 / (x_m * (1.0 - x_m));
	}
	return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
    real(8), intent (in) :: x_m
    real(8) :: tmp
    if (x_m <= 0.75d0) then
        tmp = 2.0d0
    else
        tmp = 2.0d0 / (x_m * (1.0d0 - x_m))
    end if
    code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
	double tmp;
	if (x_m <= 0.75) {
		tmp = 2.0;
	} else {
		tmp = 2.0 / (x_m * (1.0 - x_m));
	}
	return tmp;
}
x_m = math.fabs(x)
def code(x_m):
	tmp = 0
	if x_m <= 0.75:
		tmp = 2.0
	else:
		tmp = 2.0 / (x_m * (1.0 - x_m))
	return tmp
x_m = abs(x)
function code(x_m)
	tmp = 0.0
	if (x_m <= 0.75)
		tmp = 2.0;
	else
		tmp = Float64(2.0 / Float64(x_m * Float64(1.0 - x_m)));
	end
	return tmp
end
x_m = abs(x);
function tmp_2 = code(x_m)
	tmp = 0.0;
	if (x_m <= 0.75)
		tmp = 2.0;
	else
		tmp = 2.0 / (x_m * (1.0 - x_m));
	end
	tmp_2 = tmp;
end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := If[LessEqual[x$95$m, 0.75], 2.0, N[(2.0 / N[(x$95$m * N[(1.0 - x$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|

\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 0.75:\\
\;\;\;\;2\\

\mathbf{else}:\\
\;\;\;\;\frac{2}{x\_m \cdot \left(1 - x\_m\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.75

    1. Initial program 86.4%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg86.4%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative86.4%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac286.4%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub086.4%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-86.4%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub086.4%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac286.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg86.4%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative86.4%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg86.4%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified86.4%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 69.8%

      \[\leadsto \color{blue}{2} \]

    if 0.75 < x

    1. Initial program 52.3%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg52.3%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative52.3%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac252.3%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub052.3%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-52.3%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub052.3%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac252.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg52.3%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative52.3%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg52.3%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified52.3%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. flip--7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\frac{-1 \cdot -1 - x \cdot x}{-1 + x}}} \]
      2. associate-/r/7.7%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{-1 \cdot -1 - x \cdot x} \cdot \left(-1 + x\right)} \]
      3. metadata-eval7.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{1} - x \cdot x} \cdot \left(-1 + x\right) \]
      4. pow27.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{1 - \color{blue}{{x}^{2}}} \cdot \left(-1 + x\right) \]
      5. +-commutative7.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{1 - {x}^{2}} \cdot \color{blue}{\left(x + -1\right)} \]
    6. Applied egg-rr7.7%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{1 - {x}^{2}} \cdot \left(x + -1\right)} \]
    7. Step-by-step derivation
      1. associate-*l/7.6%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1 \cdot \left(x + -1\right)}{1 - {x}^{2}}} \]
      2. *-lft-identity7.6%

        \[\leadsto \frac{1}{1 - x} - \frac{\color{blue}{x + -1}}{1 - {x}^{2}} \]
    8. Simplified7.6%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{x + -1}{1 - {x}^{2}}} \]
    9. Step-by-step derivation
      1. clear-num7.8%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{\frac{1 - {x}^{2}}{x + -1}}} \]
      2. metadata-eval7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{\color{blue}{-1 \cdot -1} - {x}^{2}}{x + -1}} \]
      3. unpow27.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{-1 \cdot -1 - \color{blue}{x \cdot x}}{x + -1}} \]
      4. +-commutative7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{-1 \cdot -1 - x \cdot x}{\color{blue}{-1 + x}}} \]
      5. flip--52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1 - x}} \]
      6. frac-sub53.0%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
      7. *-un-lft-identity53.0%

        \[\leadsto \frac{\color{blue}{\left(-1 - x\right)} - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      8. *-commutative53.0%

        \[\leadsto \frac{\left(-1 - x\right) - \color{blue}{1 \cdot \left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      9. *-un-lft-identity53.0%

        \[\leadsto \frac{\left(-1 - x\right) - \color{blue}{\left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      10. associate--r+59.4%

        \[\leadsto \frac{\color{blue}{-1 - \left(x + \left(1 - x\right)\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      11. *-commutative59.4%

        \[\leadsto \frac{-1 - \left(x + \left(1 - x\right)\right)}{\color{blue}{\left(-1 - x\right) \cdot \left(1 - x\right)}} \]
      12. associate-/r*59.6%

        \[\leadsto \color{blue}{\frac{\frac{-1 - \left(x + \left(1 - x\right)\right)}{-1 - x}}{1 - x}} \]
      13. +-commutative59.6%

        \[\leadsto \frac{\frac{-1 - \color{blue}{\left(\left(1 - x\right) + x\right)}}{-1 - x}}{1 - x} \]
      14. associate--r+53.0%

        \[\leadsto \frac{\frac{\color{blue}{\left(-1 - \left(1 - x\right)\right) - x}}{-1 - x}}{1 - x} \]
    10. Applied egg-rr53.0%

      \[\leadsto \color{blue}{\frac{\frac{\left(-1 - \left(1 - x\right)\right) - x}{-1 - x}}{1 - x}} \]
    11. Taylor expanded in x around inf 98.3%

      \[\leadsto \frac{\color{blue}{\frac{2}{x}}}{1 - x} \]
    12. Step-by-step derivation
      1. *-un-lft-identity98.3%

        \[\leadsto \color{blue}{1 \cdot \frac{\frac{2}{x}}{1 - x}} \]
    13. Applied egg-rr98.3%

      \[\leadsto \color{blue}{1 \cdot \frac{\frac{2}{x}}{1 - x}} \]
    14. Step-by-step derivation
      1. *-lft-identity98.3%

        \[\leadsto \color{blue}{\frac{\frac{2}{x}}{1 - x}} \]
      2. associate-/r*96.1%

        \[\leadsto \color{blue}{\frac{2}{x \cdot \left(1 - x\right)}} \]
    15. Simplified96.1%

      \[\leadsto \color{blue}{\frac{2}{x \cdot \left(1 - x\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.75:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;\frac{2}{x \cdot \left(1 - x\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 98.3% accurate, 0.9× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ \begin{array}{l} \mathbf{if}\;x\_m \leq 0.75:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{2}{x\_m}}{1 - x\_m}\\ \end{array} \end{array} \]
x_m = (fabs.f64 x)
(FPCore (x_m)
 :precision binary64
 (if (<= x_m 0.75) 2.0 (/ (/ 2.0 x_m) (- 1.0 x_m))))
x_m = fabs(x);
double code(double x_m) {
	double tmp;
	if (x_m <= 0.75) {
		tmp = 2.0;
	} else {
		tmp = (2.0 / x_m) / (1.0 - x_m);
	}
	return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
    real(8), intent (in) :: x_m
    real(8) :: tmp
    if (x_m <= 0.75d0) then
        tmp = 2.0d0
    else
        tmp = (2.0d0 / x_m) / (1.0d0 - x_m)
    end if
    code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
	double tmp;
	if (x_m <= 0.75) {
		tmp = 2.0;
	} else {
		tmp = (2.0 / x_m) / (1.0 - x_m);
	}
	return tmp;
}
x_m = math.fabs(x)
def code(x_m):
	tmp = 0
	if x_m <= 0.75:
		tmp = 2.0
	else:
		tmp = (2.0 / x_m) / (1.0 - x_m)
	return tmp
x_m = abs(x)
function code(x_m)
	tmp = 0.0
	if (x_m <= 0.75)
		tmp = 2.0;
	else
		tmp = Float64(Float64(2.0 / x_m) / Float64(1.0 - x_m));
	end
	return tmp
end
x_m = abs(x);
function tmp_2 = code(x_m)
	tmp = 0.0;
	if (x_m <= 0.75)
		tmp = 2.0;
	else
		tmp = (2.0 / x_m) / (1.0 - x_m);
	end
	tmp_2 = tmp;
end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := If[LessEqual[x$95$m, 0.75], 2.0, N[(N[(2.0 / x$95$m), $MachinePrecision] / N[(1.0 - x$95$m), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|

\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 0.75:\\
\;\;\;\;2\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{2}{x\_m}}{1 - x\_m}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.75

    1. Initial program 86.4%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg86.4%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative86.4%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac286.4%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub086.4%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-86.4%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub086.4%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac286.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg86.4%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative86.4%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg86.4%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified86.4%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 69.8%

      \[\leadsto \color{blue}{2} \]

    if 0.75 < x

    1. Initial program 52.3%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg52.3%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative52.3%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac252.3%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub052.3%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-52.3%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub052.3%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac252.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg52.3%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative52.3%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg52.3%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified52.3%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. flip--7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\frac{-1 \cdot -1 - x \cdot x}{-1 + x}}} \]
      2. associate-/r/7.7%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{-1 \cdot -1 - x \cdot x} \cdot \left(-1 + x\right)} \]
      3. metadata-eval7.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{1} - x \cdot x} \cdot \left(-1 + x\right) \]
      4. pow27.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{1 - \color{blue}{{x}^{2}}} \cdot \left(-1 + x\right) \]
      5. +-commutative7.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{1 - {x}^{2}} \cdot \color{blue}{\left(x + -1\right)} \]
    6. Applied egg-rr7.7%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{1 - {x}^{2}} \cdot \left(x + -1\right)} \]
    7. Step-by-step derivation
      1. associate-*l/7.6%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1 \cdot \left(x + -1\right)}{1 - {x}^{2}}} \]
      2. *-lft-identity7.6%

        \[\leadsto \frac{1}{1 - x} - \frac{\color{blue}{x + -1}}{1 - {x}^{2}} \]
    8. Simplified7.6%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{x + -1}{1 - {x}^{2}}} \]
    9. Step-by-step derivation
      1. clear-num7.8%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{\frac{1 - {x}^{2}}{x + -1}}} \]
      2. metadata-eval7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{\color{blue}{-1 \cdot -1} - {x}^{2}}{x + -1}} \]
      3. unpow27.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{-1 \cdot -1 - \color{blue}{x \cdot x}}{x + -1}} \]
      4. +-commutative7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{-1 \cdot -1 - x \cdot x}{\color{blue}{-1 + x}}} \]
      5. flip--52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1 - x}} \]
      6. frac-sub53.0%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
      7. *-un-lft-identity53.0%

        \[\leadsto \frac{\color{blue}{\left(-1 - x\right)} - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      8. *-commutative53.0%

        \[\leadsto \frac{\left(-1 - x\right) - \color{blue}{1 \cdot \left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      9. *-un-lft-identity53.0%

        \[\leadsto \frac{\left(-1 - x\right) - \color{blue}{\left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      10. associate--r+59.4%

        \[\leadsto \frac{\color{blue}{-1 - \left(x + \left(1 - x\right)\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      11. *-commutative59.4%

        \[\leadsto \frac{-1 - \left(x + \left(1 - x\right)\right)}{\color{blue}{\left(-1 - x\right) \cdot \left(1 - x\right)}} \]
      12. associate-/r*59.6%

        \[\leadsto \color{blue}{\frac{\frac{-1 - \left(x + \left(1 - x\right)\right)}{-1 - x}}{1 - x}} \]
      13. +-commutative59.6%

        \[\leadsto \frac{\frac{-1 - \color{blue}{\left(\left(1 - x\right) + x\right)}}{-1 - x}}{1 - x} \]
      14. associate--r+53.0%

        \[\leadsto \frac{\frac{\color{blue}{\left(-1 - \left(1 - x\right)\right) - x}}{-1 - x}}{1 - x} \]
    10. Applied egg-rr53.0%

      \[\leadsto \color{blue}{\frac{\frac{\left(-1 - \left(1 - x\right)\right) - x}{-1 - x}}{1 - x}} \]
    11. Taylor expanded in x around inf 98.3%

      \[\leadsto \frac{\color{blue}{\frac{2}{x}}}{1 - x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.75:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{2}{x}}{1 - x}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 99.5% accurate, 1.2× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ \frac{-2}{\left(1 - x\_m\right) \cdot \left(-1 - x\_m\right)} \end{array} \]
x_m = (fabs.f64 x)
(FPCore (x_m) :precision binary64 (/ -2.0 (* (- 1.0 x_m) (- -1.0 x_m))))
x_m = fabs(x);
double code(double x_m) {
	return -2.0 / ((1.0 - x_m) * (-1.0 - x_m));
}
x_m = abs(x)
real(8) function code(x_m)
    real(8), intent (in) :: x_m
    code = (-2.0d0) / ((1.0d0 - x_m) * ((-1.0d0) - x_m))
end function
x_m = Math.abs(x);
public static double code(double x_m) {
	return -2.0 / ((1.0 - x_m) * (-1.0 - x_m));
}
x_m = math.fabs(x)
def code(x_m):
	return -2.0 / ((1.0 - x_m) * (-1.0 - x_m))
x_m = abs(x)
function code(x_m)
	return Float64(-2.0 / Float64(Float64(1.0 - x_m) * Float64(-1.0 - x_m)))
end
x_m = abs(x);
function tmp = code(x_m)
	tmp = -2.0 / ((1.0 - x_m) * (-1.0 - x_m));
end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := N[(-2.0 / N[(N[(1.0 - x$95$m), $MachinePrecision] * N[(-1.0 - x$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|

\\
\frac{-2}{\left(1 - x\_m\right) \cdot \left(-1 - x\_m\right)}
\end{array}
Derivation
  1. Initial program 76.8%

    \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
    2. +-commutative76.8%

      \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
    3. distribute-neg-frac276.8%

      \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
    4. neg-sub076.8%

      \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
    5. associate-+l-76.8%

      \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
    6. neg-sub076.8%

      \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
    7. remove-double-neg76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
    8. distribute-neg-in76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
    9. sub-neg76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
    10. distribute-neg-frac276.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
    11. sub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
    12. +-commutative76.8%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
    13. unsub-neg76.8%

      \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
    14. sub-neg76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
    15. +-commutative76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
    16. unsub-neg76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
    17. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
  3. Simplified76.8%

    \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. sub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{1 - x} + \left(-\frac{1}{-1 - x}\right)} \]
    2. distribute-neg-frac76.8%

      \[\leadsto \frac{1}{1 - x} + \color{blue}{\frac{-1}{-1 - x}} \]
    3. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} + \frac{\color{blue}{-1}}{-1 - x} \]
  6. Applied egg-rr76.8%

    \[\leadsto \color{blue}{\frac{1}{1 - x} + \frac{-1}{-1 - x}} \]
  7. Step-by-step derivation
    1. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} + \frac{\color{blue}{-1}}{-1 - x} \]
    2. distribute-neg-frac76.8%

      \[\leadsto \frac{1}{1 - x} + \color{blue}{\left(-\frac{1}{-1 - x}\right)} \]
    3. unsub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. *-rgt-identity76.8%

      \[\leadsto \color{blue}{\frac{1}{1 - x} \cdot 1} - \frac{1}{-1 - x} \]
    5. *-inverses76.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \frac{\color{blue}{\frac{-\left(1 - x\right)}{-\left(1 - x\right)}}}{-1 - x} \]
    6. associate-/r*54.1%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \color{blue}{\frac{-\left(1 - x\right)}{\left(-\left(1 - x\right)\right) \cdot \left(-1 - x\right)}} \]
    7. neg-mul-154.1%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \frac{\color{blue}{-1 \cdot \left(1 - x\right)}}{\left(-\left(1 - x\right)\right) \cdot \left(-1 - x\right)} \]
    8. times-frac76.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \color{blue}{\frac{-1}{-\left(1 - x\right)} \cdot \frac{1 - x}{-1 - x}} \]
    9. distribute-frac-neg276.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \color{blue}{\left(-\frac{-1}{1 - x}\right)} \cdot \frac{1 - x}{-1 - x} \]
    10. distribute-neg-frac76.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \color{blue}{\frac{--1}{1 - x}} \cdot \frac{1 - x}{-1 - x} \]
    11. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} \cdot 1 - \frac{\color{blue}{1}}{1 - x} \cdot \frac{1 - x}{-1 - x} \]
    12. distribute-lft-out--76.8%

      \[\leadsto \color{blue}{\frac{1}{1 - x} \cdot \left(1 - \frac{1 - x}{-1 - x}\right)} \]
    13. *-inverses76.8%

      \[\leadsto \frac{1}{1 - x} \cdot \left(\color{blue}{\frac{-1 - x}{-1 - x}} - \frac{1 - x}{-1 - x}\right) \]
    14. div-sub77.4%

      \[\leadsto \frac{1}{1 - x} \cdot \color{blue}{\frac{\left(-1 - x\right) - \left(1 - x\right)}{-1 - x}} \]
    15. associate--r+80.6%

      \[\leadsto \frac{1}{1 - x} \cdot \frac{\color{blue}{-1 - \left(x + \left(1 - x\right)\right)}}{-1 - x} \]
    16. associate-*r/80.6%

      \[\leadsto \color{blue}{\frac{\frac{1}{1 - x} \cdot \left(-1 - \left(x + \left(1 - x\right)\right)\right)}{-1 - x}} \]
    17. associate-*l/80.6%

      \[\leadsto \color{blue}{\frac{\frac{1}{1 - x}}{-1 - x} \cdot \left(-1 - \left(x + \left(1 - x\right)\right)\right)} \]
  8. Simplified99.2%

    \[\leadsto \color{blue}{\frac{-2}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
  9. Final simplification99.2%

    \[\leadsto \frac{-2}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
  10. Add Preprocessing

Alternative 5: 75.1% accurate, 1.8× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ \begin{array}{l} \mathbf{if}\;x\_m \leq 1:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \end{array} \]
x_m = (fabs.f64 x)
(FPCore (x_m) :precision binary64 (if (<= x_m 1.0) 2.0 0.0))
x_m = fabs(x);
double code(double x_m) {
	double tmp;
	if (x_m <= 1.0) {
		tmp = 2.0;
	} else {
		tmp = 0.0;
	}
	return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
    real(8), intent (in) :: x_m
    real(8) :: tmp
    if (x_m <= 1.0d0) then
        tmp = 2.0d0
    else
        tmp = 0.0d0
    end if
    code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
	double tmp;
	if (x_m <= 1.0) {
		tmp = 2.0;
	} else {
		tmp = 0.0;
	}
	return tmp;
}
x_m = math.fabs(x)
def code(x_m):
	tmp = 0
	if x_m <= 1.0:
		tmp = 2.0
	else:
		tmp = 0.0
	return tmp
x_m = abs(x)
function code(x_m)
	tmp = 0.0
	if (x_m <= 1.0)
		tmp = 2.0;
	else
		tmp = 0.0;
	end
	return tmp
end
x_m = abs(x);
function tmp_2 = code(x_m)
	tmp = 0.0;
	if (x_m <= 1.0)
		tmp = 2.0;
	else
		tmp = 0.0;
	end
	tmp_2 = tmp;
end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := If[LessEqual[x$95$m, 1.0], 2.0, 0.0]
\begin{array}{l}
x_m = \left|x\right|

\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 1:\\
\;\;\;\;2\\

\mathbf{else}:\\
\;\;\;\;0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1

    1. Initial program 86.4%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg86.4%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative86.4%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac286.4%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub086.4%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-86.4%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub086.4%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg86.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac286.4%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg86.4%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative86.4%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg86.4%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval86.4%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified86.4%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 69.8%

      \[\leadsto \color{blue}{2} \]

    if 1 < x

    1. Initial program 52.3%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg52.3%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative52.3%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac252.3%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub052.3%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-52.3%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub052.3%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg52.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac252.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg52.3%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative52.3%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg52.3%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified52.3%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. flip--7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\frac{-1 \cdot -1 - x \cdot x}{-1 + x}}} \]
      2. associate-/r/7.7%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{-1 \cdot -1 - x \cdot x} \cdot \left(-1 + x\right)} \]
      3. metadata-eval7.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{1} - x \cdot x} \cdot \left(-1 + x\right) \]
      4. pow27.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{1 - \color{blue}{{x}^{2}}} \cdot \left(-1 + x\right) \]
      5. +-commutative7.7%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{1 - {x}^{2}} \cdot \color{blue}{\left(x + -1\right)} \]
    6. Applied egg-rr7.7%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{1 - {x}^{2}} \cdot \left(x + -1\right)} \]
    7. Step-by-step derivation
      1. associate-*l/7.6%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1 \cdot \left(x + -1\right)}{1 - {x}^{2}}} \]
      2. *-lft-identity7.6%

        \[\leadsto \frac{1}{1 - x} - \frac{\color{blue}{x + -1}}{1 - {x}^{2}} \]
    8. Simplified7.6%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{x + -1}{1 - {x}^{2}}} \]
    9. Step-by-step derivation
      1. clear-num7.8%

        \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{\frac{1 - {x}^{2}}{x + -1}}} \]
      2. metadata-eval7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{\color{blue}{-1 \cdot -1} - {x}^{2}}{x + -1}} \]
      3. unpow27.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{-1 \cdot -1 - \color{blue}{x \cdot x}}{x + -1}} \]
      4. +-commutative7.8%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{-1 \cdot -1 - x \cdot x}{\color{blue}{-1 + x}}} \]
      5. flip--52.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1 - x}} \]
      6. frac-sub53.0%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
      7. *-un-lft-identity53.0%

        \[\leadsto \frac{\color{blue}{\left(-1 - x\right)} - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      8. *-commutative53.0%

        \[\leadsto \frac{\left(-1 - x\right) - \color{blue}{1 \cdot \left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      9. *-un-lft-identity53.0%

        \[\leadsto \frac{\left(-1 - x\right) - \color{blue}{\left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      10. associate--r+59.4%

        \[\leadsto \frac{\color{blue}{-1 - \left(x + \left(1 - x\right)\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      11. flip--56.7%

        \[\leadsto \frac{\color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{-1 + \left(x + \left(1 - x\right)\right)}}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      12. associate-/l/56.7%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)}} \]
      13. metadata-eval56.7%

        \[\leadsto \frac{\color{blue}{1} - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      14. pow256.7%

        \[\leadsto \frac{1 - \color{blue}{{\left(x + \left(1 - x\right)\right)}^{2}}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    10. Applied egg-rr56.7%

      \[\leadsto \color{blue}{\frac{1 - {\left(x + \left(1 - x\right)\right)}^{2}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)}} \]
    11. Step-by-step derivation
      1. div-sub56.7%

        \[\leadsto \color{blue}{\frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{{\left(x + \left(1 - x\right)\right)}^{2}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)}} \]
      2. unpow256.7%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{\left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      3. +-commutative56.7%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      4. associate--r-56.7%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      5. +-inverses56.7%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\left(1 - \color{blue}{0}\right) \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      6. metadata-eval56.7%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{1} \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      7. +-commutative56.7%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{1 \cdot \color{blue}{\left(\left(1 - x\right) + x\right)}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      8. associate--r-50.2%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{1 \cdot \color{blue}{\left(1 - \left(x - x\right)\right)}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      9. +-inverses50.2%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{1 \cdot \left(1 - \color{blue}{0}\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      10. metadata-eval50.2%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{1 \cdot \color{blue}{1}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      11. metadata-eval50.2%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{1}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
      12. +-inverses50.3%

        \[\leadsto \color{blue}{0} \]
    12. Simplified50.3%

      \[\leadsto \color{blue}{0} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 27.3% accurate, 11.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ 0 \end{array} \]
x_m = (fabs.f64 x)
(FPCore (x_m) :precision binary64 0.0)
x_m = fabs(x);
double code(double x_m) {
	return 0.0;
}
x_m = abs(x)
real(8) function code(x_m)
    real(8), intent (in) :: x_m
    code = 0.0d0
end function
x_m = Math.abs(x);
public static double code(double x_m) {
	return 0.0;
}
x_m = math.fabs(x)
def code(x_m):
	return 0.0
x_m = abs(x)
function code(x_m)
	return 0.0
end
x_m = abs(x);
function tmp = code(x_m)
	tmp = 0.0;
end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := 0.0
\begin{array}{l}
x_m = \left|x\right|

\\
0
\end{array}
Derivation
  1. Initial program 76.8%

    \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
    2. +-commutative76.8%

      \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
    3. distribute-neg-frac276.8%

      \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
    4. neg-sub076.8%

      \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
    5. associate-+l-76.8%

      \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
    6. neg-sub076.8%

      \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
    7. remove-double-neg76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
    8. distribute-neg-in76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
    9. sub-neg76.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
    10. distribute-neg-frac276.8%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
    11. sub-neg76.8%

      \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
    12. +-commutative76.8%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
    13. unsub-neg76.8%

      \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
    14. sub-neg76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
    15. +-commutative76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
    16. unsub-neg76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
    17. metadata-eval76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
  3. Simplified76.8%

    \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. flip--54.2%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\frac{-1 \cdot -1 - x \cdot x}{-1 + x}}} \]
    2. associate-/r/54.1%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{-1 \cdot -1 - x \cdot x} \cdot \left(-1 + x\right)} \]
    3. metadata-eval54.1%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{1} - x \cdot x} \cdot \left(-1 + x\right) \]
    4. pow254.1%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{1 - \color{blue}{{x}^{2}}} \cdot \left(-1 + x\right) \]
    5. +-commutative54.1%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{1 - {x}^{2}} \cdot \color{blue}{\left(x + -1\right)} \]
  6. Applied egg-rr54.1%

    \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{1 - {x}^{2}} \cdot \left(x + -1\right)} \]
  7. Step-by-step derivation
    1. associate-*l/54.1%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1 \cdot \left(x + -1\right)}{1 - {x}^{2}}} \]
    2. *-lft-identity54.1%

      \[\leadsto \frac{1}{1 - x} - \frac{\color{blue}{x + -1}}{1 - {x}^{2}} \]
  8. Simplified54.1%

    \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{x + -1}{1 - {x}^{2}}} \]
  9. Step-by-step derivation
    1. clear-num54.2%

      \[\leadsto \frac{1}{1 - x} - \color{blue}{\frac{1}{\frac{1 - {x}^{2}}{x + -1}}} \]
    2. metadata-eval54.2%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{\color{blue}{-1 \cdot -1} - {x}^{2}}{x + -1}} \]
    3. unpow254.2%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{-1 \cdot -1 - \color{blue}{x \cdot x}}{x + -1}} \]
    4. +-commutative54.2%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\frac{-1 \cdot -1 - x \cdot x}{\color{blue}{-1 + x}}} \]
    5. flip--76.8%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1 - x}} \]
    6. frac-sub77.4%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
    7. *-un-lft-identity77.4%

      \[\leadsto \frac{\color{blue}{\left(-1 - x\right)} - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    8. *-commutative77.4%

      \[\leadsto \frac{\left(-1 - x\right) - \color{blue}{1 \cdot \left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    9. *-un-lft-identity77.4%

      \[\leadsto \frac{\left(-1 - x\right) - \color{blue}{\left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    10. associate--r+80.6%

      \[\leadsto \frac{\color{blue}{-1 - \left(x + \left(1 - x\right)\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    11. flip--28.6%

      \[\leadsto \frac{\color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{-1 + \left(x + \left(1 - x\right)\right)}}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    12. associate-/l/28.6%

      \[\leadsto \color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)}} \]
    13. metadata-eval28.6%

      \[\leadsto \frac{\color{blue}{1} - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    14. pow228.6%

      \[\leadsto \frac{1 - \color{blue}{{\left(x + \left(1 - x\right)\right)}^{2}}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
  10. Applied egg-rr28.6%

    \[\leadsto \color{blue}{\frac{1 - {\left(x + \left(1 - x\right)\right)}^{2}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)}} \]
  11. Step-by-step derivation
    1. div-sub28.6%

      \[\leadsto \color{blue}{\frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{{\left(x + \left(1 - x\right)\right)}^{2}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)}} \]
    2. unpow228.6%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{\left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    3. +-commutative28.6%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    4. associate--r-28.6%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    5. +-inverses28.6%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\left(1 - \color{blue}{0}\right) \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    6. metadata-eval28.6%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{1} \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    7. +-commutative28.6%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{1 \cdot \color{blue}{\left(\left(1 - x\right) + x\right)}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    8. associate--r-25.4%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{1 \cdot \color{blue}{\left(1 - \left(x - x\right)\right)}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    9. +-inverses25.4%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{1 \cdot \left(1 - \color{blue}{0}\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    10. metadata-eval25.4%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{1 \cdot \color{blue}{1}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    11. metadata-eval25.4%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} - \frac{\color{blue}{1}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)} \]
    12. +-inverses27.1%

      \[\leadsto \color{blue}{0} \]
  12. Simplified27.1%

    \[\leadsto \color{blue}{0} \]
  13. Final simplification27.1%

    \[\leadsto 0 \]
  14. Add Preprocessing

Reproduce

?
herbie shell --seed 2024112 
(FPCore (x)
  :name "Asymptote A"
  :precision binary64
  (- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))