3frac (problem 3.3.3)

Percentage Accurate: 69.2% → 99.7%
Time: 8.9s
Alternatives: 10
Speedup: 1.7×

Specification

?
\[\left|x\right| > 1\]
\[\begin{array}{l} \\ \left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \end{array} \]
(FPCore (x)
 :precision binary64
 (+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))
double code(double x) {
	return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((1.0d0 / (x + 1.0d0)) - (2.0d0 / x)) + (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
	return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
def code(x):
	return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0))
function code(x)
	return Float64(Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(2.0 / x)) + Float64(1.0 / Float64(x - 1.0)))
end
function tmp = code(x)
	tmp = ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
end
code[x_] := N[(N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(2.0 / x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \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 10 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: 69.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \end{array} \]
(FPCore (x)
 :precision binary64
 (+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))
double code(double x) {
	return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((1.0d0 / (x + 1.0d0)) - (2.0d0 / x)) + (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
	return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
def code(x):
	return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0))
function code(x)
	return Float64(Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(2.0 / x)) + Float64(1.0 / Float64(x - 1.0)))
end
function tmp = code(x)
	tmp = ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
end
code[x_] := N[(N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(2.0 / x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1}
\end{array}

Alternative 1: 99.7% accurate, 0.0× speedup?

\[\begin{array}{l} \\ \left(2 + \mathsf{fma}\left(2, {x}^{-2}, 2 \cdot \left({x}^{-6} + {x}^{-4}\right)\right)\right) \cdot {x}^{-3} \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  (+ 2.0 (fma 2.0 (pow x -2.0) (* 2.0 (+ (pow x -6.0) (pow x -4.0)))))
  (pow x -3.0)))
double code(double x) {
	return (2.0 + fma(2.0, pow(x, -2.0), (2.0 * (pow(x, -6.0) + pow(x, -4.0))))) * pow(x, -3.0);
}
function code(x)
	return Float64(Float64(2.0 + fma(2.0, (x ^ -2.0), Float64(2.0 * Float64((x ^ -6.0) + (x ^ -4.0))))) * (x ^ -3.0))
end
code[x_] := N[(N[(2.0 + N[(2.0 * N[Power[x, -2.0], $MachinePrecision] + N[(2.0 * N[(N[Power[x, -6.0], $MachinePrecision] + N[Power[x, -4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Power[x, -3.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(2 + \mathsf{fma}\left(2, {x}^{-2}, 2 \cdot \left({x}^{-6} + {x}^{-4}\right)\right)\right) \cdot {x}^{-3}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 98.9%

    \[\leadsto \color{blue}{\frac{2 + \left(2 \cdot \frac{1}{{x}^{2}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. associate-*r/98.9%

      \[\leadsto \frac{2 + \left(\color{blue}{\frac{2 \cdot 1}{{x}^{2}}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}} \]
    2. metadata-eval98.9%

      \[\leadsto \frac{2 + \left(\frac{\color{blue}{2}}{{x}^{2}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}} \]
    3. +-commutative98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \color{blue}{\left(\frac{2}{{x}^{4}} + 2 \cdot \frac{1}{{x}^{6}}\right)}\right)}{{x}^{3}} \]
    4. associate-*r/98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \color{blue}{\frac{2 \cdot 1}{{x}^{6}}}\right)\right)}{{x}^{3}} \]
    5. metadata-eval98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{\color{blue}{2}}{{x}^{6}}\right)\right)}{{x}^{3}} \]
  7. Simplified98.9%

    \[\leadsto \color{blue}{\frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)}{{x}^{3}}} \]
  8. Step-by-step derivation
    1. div-inv98.9%

      \[\leadsto \color{blue}{\left(2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)\right) \cdot \frac{1}{{x}^{3}}} \]
    2. div-inv98.9%

      \[\leadsto \left(2 + \left(\color{blue}{2 \cdot \frac{1}{{x}^{2}}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    3. fma-define98.9%

      \[\leadsto \left(2 + \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)}\right) \cdot \frac{1}{{x}^{3}} \]
    4. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    5. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{\color{blue}{-2}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    6. +-commutative98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{\frac{2}{{x}^{6}} + \frac{2}{{x}^{4}}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    7. div-inv98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot \frac{1}{{x}^{6}}} + \frac{2}{{x}^{4}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    8. fma-define98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{6}}, \frac{2}{{x}^{4}}\right)}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    9. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-6\right)}}, \frac{2}{{x}^{4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    10. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{\color{blue}{-6}}, \frac{2}{{x}^{4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    11. div-inv98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, \color{blue}{2 \cdot \frac{1}{{x}^{4}}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    12. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot \color{blue}{{x}^{\left(-4\right)}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    13. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{\color{blue}{-4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    14. pow-flip99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot \color{blue}{{x}^{\left(-3\right)}} \]
    15. metadata-eval99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot {x}^{\color{blue}{-3}} \]
  9. Applied egg-rr99.9%

    \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot {x}^{-3}} \]
  10. Step-by-step derivation
    1. *-lft-identity99.9%

      \[\leadsto \color{blue}{\left(1 \cdot \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right)\right)} \cdot {x}^{-3} \]
    2. *-lft-identity99.9%

      \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right)} \cdot {x}^{-3} \]
    3. fma-undefine99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot {x}^{-6} + 2 \cdot {x}^{-4}}\right)\right) \cdot {x}^{-3} \]
    4. distribute-lft-out99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot \left({x}^{-6} + {x}^{-4}\right)}\right)\right) \cdot {x}^{-3} \]
  11. Simplified99.9%

    \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, 2 \cdot \left({x}^{-6} + {x}^{-4}\right)\right)\right) \cdot {x}^{-3}} \]
  12. Add Preprocessing

Alternative 2: 99.7% accurate, 0.0× speedup?

\[\begin{array}{l} \\ {x}^{-3} \cdot \left(2 + \frac{2 + \frac{2}{{x}^{2}}}{{x}^{2}}\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (* (pow x -3.0) (+ 2.0 (/ (+ 2.0 (/ 2.0 (pow x 2.0))) (pow x 2.0)))))
double code(double x) {
	return pow(x, -3.0) * (2.0 + ((2.0 + (2.0 / pow(x, 2.0))) / pow(x, 2.0)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x ** (-3.0d0)) * (2.0d0 + ((2.0d0 + (2.0d0 / (x ** 2.0d0))) / (x ** 2.0d0)))
end function
public static double code(double x) {
	return Math.pow(x, -3.0) * (2.0 + ((2.0 + (2.0 / Math.pow(x, 2.0))) / Math.pow(x, 2.0)));
}
def code(x):
	return math.pow(x, -3.0) * (2.0 + ((2.0 + (2.0 / math.pow(x, 2.0))) / math.pow(x, 2.0)))
function code(x)
	return Float64((x ^ -3.0) * Float64(2.0 + Float64(Float64(2.0 + Float64(2.0 / (x ^ 2.0))) / (x ^ 2.0))))
end
function tmp = code(x)
	tmp = (x ^ -3.0) * (2.0 + ((2.0 + (2.0 / (x ^ 2.0))) / (x ^ 2.0)));
end
code[x_] := N[(N[Power[x, -3.0], $MachinePrecision] * N[(2.0 + N[(N[(2.0 + N[(2.0 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
{x}^{-3} \cdot \left(2 + \frac{2 + \frac{2}{{x}^{2}}}{{x}^{2}}\right)
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 98.9%

    \[\leadsto \color{blue}{\frac{2 + \left(2 \cdot \frac{1}{{x}^{2}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. associate-*r/98.9%

      \[\leadsto \frac{2 + \left(\color{blue}{\frac{2 \cdot 1}{{x}^{2}}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}} \]
    2. metadata-eval98.9%

      \[\leadsto \frac{2 + \left(\frac{\color{blue}{2}}{{x}^{2}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}} \]
    3. +-commutative98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \color{blue}{\left(\frac{2}{{x}^{4}} + 2 \cdot \frac{1}{{x}^{6}}\right)}\right)}{{x}^{3}} \]
    4. associate-*r/98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \color{blue}{\frac{2 \cdot 1}{{x}^{6}}}\right)\right)}{{x}^{3}} \]
    5. metadata-eval98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{\color{blue}{2}}{{x}^{6}}\right)\right)}{{x}^{3}} \]
  7. Simplified98.9%

    \[\leadsto \color{blue}{\frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)}{{x}^{3}}} \]
  8. Step-by-step derivation
    1. div-inv98.9%

      \[\leadsto \color{blue}{\left(2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)\right) \cdot \frac{1}{{x}^{3}}} \]
    2. div-inv98.9%

      \[\leadsto \left(2 + \left(\color{blue}{2 \cdot \frac{1}{{x}^{2}}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    3. fma-define98.9%

      \[\leadsto \left(2 + \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)}\right) \cdot \frac{1}{{x}^{3}} \]
    4. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    5. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{\color{blue}{-2}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    6. +-commutative98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{\frac{2}{{x}^{6}} + \frac{2}{{x}^{4}}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    7. div-inv98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot \frac{1}{{x}^{6}}} + \frac{2}{{x}^{4}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    8. fma-define98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{6}}, \frac{2}{{x}^{4}}\right)}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    9. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-6\right)}}, \frac{2}{{x}^{4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    10. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{\color{blue}{-6}}, \frac{2}{{x}^{4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    11. div-inv98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, \color{blue}{2 \cdot \frac{1}{{x}^{4}}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    12. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot \color{blue}{{x}^{\left(-4\right)}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    13. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{\color{blue}{-4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    14. pow-flip99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot \color{blue}{{x}^{\left(-3\right)}} \]
    15. metadata-eval99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot {x}^{\color{blue}{-3}} \]
  9. Applied egg-rr99.9%

    \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot {x}^{-3}} \]
  10. Step-by-step derivation
    1. *-lft-identity99.9%

      \[\leadsto \color{blue}{\left(1 \cdot \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right)\right)} \cdot {x}^{-3} \]
    2. *-lft-identity99.9%

      \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right)} \cdot {x}^{-3} \]
    3. fma-undefine99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot {x}^{-6} + 2 \cdot {x}^{-4}}\right)\right) \cdot {x}^{-3} \]
    4. distribute-lft-out99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot \left({x}^{-6} + {x}^{-4}\right)}\right)\right) \cdot {x}^{-3} \]
  11. Simplified99.9%

    \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, 2 \cdot \left({x}^{-6} + {x}^{-4}\right)\right)\right) \cdot {x}^{-3}} \]
  12. Taylor expanded in x around inf 99.8%

    \[\leadsto \left(2 + \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{2}}}\right) \cdot {x}^{-3} \]
  13. Step-by-step derivation
    1. associate-*r/99.8%

      \[\leadsto \left(2 + \frac{2 + \color{blue}{\frac{2 \cdot 1}{{x}^{2}}}}{{x}^{2}}\right) \cdot {x}^{-3} \]
    2. metadata-eval99.8%

      \[\leadsto \left(2 + \frac{2 + \frac{\color{blue}{2}}{{x}^{2}}}{{x}^{2}}\right) \cdot {x}^{-3} \]
  14. Simplified99.8%

    \[\leadsto \left(2 + \color{blue}{\frac{2 + \frac{2}{{x}^{2}}}{{x}^{2}}}\right) \cdot {x}^{-3} \]
  15. Final simplification99.8%

    \[\leadsto {x}^{-3} \cdot \left(2 + \frac{2 + \frac{2}{{x}^{2}}}{{x}^{2}}\right) \]
  16. Add Preprocessing

Alternative 3: 99.2% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \frac{-2}{x \cdot \left(1 - {x}^{2}\right)} \end{array} \]
(FPCore (x) :precision binary64 (/ -2.0 (* x (- 1.0 (pow x 2.0)))))
double code(double x) {
	return -2.0 / (x * (1.0 - pow(x, 2.0)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (-2.0d0) / (x * (1.0d0 - (x ** 2.0d0)))
end function
public static double code(double x) {
	return -2.0 / (x * (1.0 - Math.pow(x, 2.0)));
}
def code(x):
	return -2.0 / (x * (1.0 - math.pow(x, 2.0)))
function code(x)
	return Float64(-2.0 / Float64(x * Float64(1.0 - (x ^ 2.0))))
end
function tmp = code(x)
	tmp = -2.0 / (x * (1.0 - (x ^ 2.0)));
end
code[x_] := N[(-2.0 / N[(x * N[(1.0 - N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{-2}{x \cdot \left(1 - {x}^{2}\right)}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. frac-sub19.4%

      \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-2 \cdot \left(-1 - x\right) - x \cdot 1}{x \cdot \left(-1 - x\right)}} \]
    2. frac-add21.0%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(x \cdot \left(-1 - x\right)\right) + \left(x + -1\right) \cdot \left(-2 \cdot \left(-1 - x\right) - x \cdot 1\right)}{\left(x + -1\right) \cdot \left(x \cdot \left(-1 - x\right)\right)}} \]
    3. *-un-lft-identity21.0%

      \[\leadsto \frac{\color{blue}{x \cdot \left(-1 - x\right)} + \left(x + -1\right) \cdot \left(-2 \cdot \left(-1 - x\right) - x \cdot 1\right)}{\left(x + -1\right) \cdot \left(x \cdot \left(-1 - x\right)\right)} \]
    4. fma-define20.0%

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(x, -1 - x, \left(x + -1\right) \cdot \left(-2 \cdot \left(-1 - x\right) - x \cdot 1\right)\right)}}{\left(x + -1\right) \cdot \left(x \cdot \left(-1 - x\right)\right)} \]
    5. *-rgt-identity20.0%

      \[\leadsto \frac{\mathsf{fma}\left(x, -1 - x, \left(x + -1\right) \cdot \left(-2 \cdot \left(-1 - x\right) - \color{blue}{x}\right)\right)}{\left(x + -1\right) \cdot \left(x \cdot \left(-1 - x\right)\right)} \]
    6. fma-neg20.0%

      \[\leadsto \frac{\mathsf{fma}\left(x, -1 - x, \left(x + -1\right) \cdot \color{blue}{\mathsf{fma}\left(-2, -1 - x, -x\right)}\right)}{\left(x + -1\right) \cdot \left(x \cdot \left(-1 - x\right)\right)} \]
  6. Applied egg-rr20.0%

    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(x, -1 - x, \left(x + -1\right) \cdot \mathsf{fma}\left(-2, -1 - x, -x\right)\right)}{\left(x + -1\right) \cdot \left(x \cdot \left(-1 - x\right)\right)}} \]
  7. Simplified20.0%

    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(x + -1, \left(2 + 2 \cdot x\right) - x, x \cdot \left(-1 - x\right)\right)}{x \cdot \left(1 - {x}^{2}\right)}} \]
  8. Taylor expanded in x around 0 98.9%

    \[\leadsto \frac{\color{blue}{-2}}{x \cdot \left(1 - {x}^{2}\right)} \]
  9. Add Preprocessing

Alternative 4: 98.9% accurate, 0.1× speedup?

\[\begin{array}{l} \\ 2 \cdot {x}^{-3} \end{array} \]
(FPCore (x) :precision binary64 (* 2.0 (pow x -3.0)))
double code(double x) {
	return 2.0 * pow(x, -3.0);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 2.0d0 * (x ** (-3.0d0))
end function
public static double code(double x) {
	return 2.0 * Math.pow(x, -3.0);
}
def code(x):
	return 2.0 * math.pow(x, -3.0)
function code(x)
	return Float64(2.0 * (x ^ -3.0))
end
function tmp = code(x)
	tmp = 2.0 * (x ^ -3.0);
end
code[x_] := N[(2.0 * N[Power[x, -3.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
2 \cdot {x}^{-3}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 98.9%

    \[\leadsto \color{blue}{\frac{2 + \left(2 \cdot \frac{1}{{x}^{2}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. associate-*r/98.9%

      \[\leadsto \frac{2 + \left(\color{blue}{\frac{2 \cdot 1}{{x}^{2}}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}} \]
    2. metadata-eval98.9%

      \[\leadsto \frac{2 + \left(\frac{\color{blue}{2}}{{x}^{2}} + \left(2 \cdot \frac{1}{{x}^{6}} + \frac{2}{{x}^{4}}\right)\right)}{{x}^{3}} \]
    3. +-commutative98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \color{blue}{\left(\frac{2}{{x}^{4}} + 2 \cdot \frac{1}{{x}^{6}}\right)}\right)}{{x}^{3}} \]
    4. associate-*r/98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \color{blue}{\frac{2 \cdot 1}{{x}^{6}}}\right)\right)}{{x}^{3}} \]
    5. metadata-eval98.9%

      \[\leadsto \frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{\color{blue}{2}}{{x}^{6}}\right)\right)}{{x}^{3}} \]
  7. Simplified98.9%

    \[\leadsto \color{blue}{\frac{2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)}{{x}^{3}}} \]
  8. Step-by-step derivation
    1. div-inv98.9%

      \[\leadsto \color{blue}{\left(2 + \left(\frac{2}{{x}^{2}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)\right) \cdot \frac{1}{{x}^{3}}} \]
    2. div-inv98.9%

      \[\leadsto \left(2 + \left(\color{blue}{2 \cdot \frac{1}{{x}^{2}}} + \left(\frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    3. fma-define98.9%

      \[\leadsto \left(2 + \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)}\right) \cdot \frac{1}{{x}^{3}} \]
    4. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    5. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{\color{blue}{-2}}, \frac{2}{{x}^{4}} + \frac{2}{{x}^{6}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    6. +-commutative98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{\frac{2}{{x}^{6}} + \frac{2}{{x}^{4}}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    7. div-inv98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot \frac{1}{{x}^{6}}} + \frac{2}{{x}^{4}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    8. fma-define98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{6}}, \frac{2}{{x}^{4}}\right)}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    9. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-6\right)}}, \frac{2}{{x}^{4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    10. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{\color{blue}{-6}}, \frac{2}{{x}^{4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    11. div-inv98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, \color{blue}{2 \cdot \frac{1}{{x}^{4}}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    12. pow-flip98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot \color{blue}{{x}^{\left(-4\right)}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    13. metadata-eval98.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{\color{blue}{-4}}\right)\right)\right) \cdot \frac{1}{{x}^{3}} \]
    14. pow-flip99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot \color{blue}{{x}^{\left(-3\right)}} \]
    15. metadata-eval99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot {x}^{\color{blue}{-3}} \]
  9. Applied egg-rr99.9%

    \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right) \cdot {x}^{-3}} \]
  10. Step-by-step derivation
    1. *-lft-identity99.9%

      \[\leadsto \color{blue}{\left(1 \cdot \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right)\right)} \cdot {x}^{-3} \]
    2. *-lft-identity99.9%

      \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-6}, 2 \cdot {x}^{-4}\right)\right)\right)} \cdot {x}^{-3} \]
    3. fma-undefine99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot {x}^{-6} + 2 \cdot {x}^{-4}}\right)\right) \cdot {x}^{-3} \]
    4. distribute-lft-out99.9%

      \[\leadsto \left(2 + \mathsf{fma}\left(2, {x}^{-2}, \color{blue}{2 \cdot \left({x}^{-6} + {x}^{-4}\right)}\right)\right) \cdot {x}^{-3} \]
  11. Simplified99.9%

    \[\leadsto \color{blue}{\left(2 + \mathsf{fma}\left(2, {x}^{-2}, 2 \cdot \left({x}^{-6} + {x}^{-4}\right)\right)\right) \cdot {x}^{-3}} \]
  12. Taylor expanded in x around inf 98.6%

    \[\leadsto \color{blue}{2} \cdot {x}^{-3} \]
  13. Add Preprocessing

Alternative 5: 72.1% accurate, 1.7× speedup?

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

\\
\frac{\frac{1}{x}}{x \cdot \left(x + -1\right)}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. clear-num70.6%

      \[\leadsto \frac{1}{x + -1} + \left(\color{blue}{\frac{1}{\frac{x}{-2}}} - \frac{1}{-1 - x}\right) \]
    2. frac-sub19.4%

      \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{1 \cdot \left(-1 - x\right) - \frac{x}{-2} \cdot 1}{\frac{x}{-2} \cdot \left(-1 - x\right)}} \]
    3. *-un-lft-identity19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\color{blue}{\left(-1 - x\right)} - \frac{x}{-2} \cdot 1}{\frac{x}{-2} \cdot \left(-1 - x\right)} \]
    4. div-inv19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\left(-1 - x\right) - \color{blue}{\left(x \cdot \frac{1}{-2}\right)} \cdot 1}{\frac{x}{-2} \cdot \left(-1 - x\right)} \]
    5. metadata-eval19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\left(-1 - x\right) - \left(x \cdot \color{blue}{-0.5}\right) \cdot 1}{\frac{x}{-2} \cdot \left(-1 - x\right)} \]
    6. div-inv19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\left(-1 - x\right) - \left(x \cdot -0.5\right) \cdot 1}{\color{blue}{\left(x \cdot \frac{1}{-2}\right)} \cdot \left(-1 - x\right)} \]
    7. metadata-eval19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\left(-1 - x\right) - \left(x \cdot -0.5\right) \cdot 1}{\left(x \cdot \color{blue}{-0.5}\right) \cdot \left(-1 - x\right)} \]
  6. Applied egg-rr19.4%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{\left(-1 - x\right) - \left(x \cdot -0.5\right) \cdot 1}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)}} \]
  7. Step-by-step derivation
    1. sub-neg19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\color{blue}{\left(-1 - x\right) + \left(-\left(x \cdot -0.5\right) \cdot 1\right)}}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    2. sub-neg19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\color{blue}{\left(-1 + \left(-x\right)\right)} + \left(-\left(x \cdot -0.5\right) \cdot 1\right)}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    3. distribute-rgt-neg-in19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\left(-1 + \left(-x\right)\right) + \color{blue}{\left(x \cdot -0.5\right) \cdot \left(-1\right)}}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    4. metadata-eval19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\left(-1 + \left(-x\right)\right) + \left(x \cdot -0.5\right) \cdot \color{blue}{-1}}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    5. associate-+l+19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{\color{blue}{-1 + \left(\left(-x\right) + \left(x \cdot -0.5\right) \cdot -1\right)}}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    6. neg-mul-119.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + \left(\color{blue}{-1 \cdot x} + \left(x \cdot -0.5\right) \cdot -1\right)}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    7. *-commutative19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + \left(\color{blue}{x \cdot -1} + \left(x \cdot -0.5\right) \cdot -1\right)}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    8. associate-*l*19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + \left(x \cdot -1 + \color{blue}{x \cdot \left(-0.5 \cdot -1\right)}\right)}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    9. distribute-lft-out19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + \color{blue}{x \cdot \left(-1 + -0.5 \cdot -1\right)}}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    10. metadata-eval19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot \left(-1 + \color{blue}{0.5}\right)}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    11. metadata-eval19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot \color{blue}{-0.5}}{\left(x \cdot -0.5\right) \cdot \left(-1 - x\right)} \]
    12. associate-*l*19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot -0.5}{\color{blue}{x \cdot \left(-0.5 \cdot \left(-1 - x\right)\right)}} \]
    13. sub-neg19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot -0.5}{x \cdot \left(-0.5 \cdot \color{blue}{\left(-1 + \left(-x\right)\right)}\right)} \]
    14. +-commutative19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot -0.5}{x \cdot \left(-0.5 \cdot \color{blue}{\left(\left(-x\right) + -1\right)}\right)} \]
    15. distribute-rgt-in19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot -0.5}{x \cdot \color{blue}{\left(\left(-x\right) \cdot -0.5 + -1 \cdot -0.5\right)}} \]
    16. distribute-lft-neg-in19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot -0.5}{x \cdot \left(\color{blue}{\left(-x \cdot -0.5\right)} + -1 \cdot -0.5\right)} \]
    17. distribute-rgt-neg-in19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot -0.5}{x \cdot \left(\color{blue}{x \cdot \left(--0.5\right)} + -1 \cdot -0.5\right)} \]
    18. metadata-eval19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot -0.5}{x \cdot \left(x \cdot \color{blue}{0.5} + -1 \cdot -0.5\right)} \]
    19. metadata-eval19.4%

      \[\leadsto \frac{1}{x + -1} + \frac{-1 + x \cdot -0.5}{x \cdot \left(x \cdot 0.5 + \color{blue}{0.5}\right)} \]
  8. Simplified19.4%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1 + x \cdot -0.5}{x \cdot \left(x \cdot 0.5 + 0.5\right)}} \]
  9. Taylor expanded in x around inf 69.2%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{-1 \cdot \frac{1 + \frac{1}{x}}{x}} \]
  10. Step-by-step derivation
    1. associate-*r/69.2%

      \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1 \cdot \left(1 + \frac{1}{x}\right)}{x}} \]
    2. neg-mul-169.2%

      \[\leadsto \frac{1}{x + -1} + \frac{\color{blue}{-\left(1 + \frac{1}{x}\right)}}{x} \]
    3. distribute-neg-in69.2%

      \[\leadsto \frac{1}{x + -1} + \frac{\color{blue}{\left(-1\right) + \left(-\frac{1}{x}\right)}}{x} \]
    4. metadata-eval69.2%

      \[\leadsto \frac{1}{x + -1} + \frac{\color{blue}{-1} + \left(-\frac{1}{x}\right)}{x} \]
    5. sub-neg69.2%

      \[\leadsto \frac{1}{x + -1} + \frac{\color{blue}{-1 - \frac{1}{x}}}{x} \]
  11. Simplified69.2%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1 - \frac{1}{x}}{x}} \]
  12. Step-by-step derivation
    1. frac-add69.2%

      \[\leadsto \color{blue}{\frac{1 \cdot x + \left(x + -1\right) \cdot \left(-1 - \frac{1}{x}\right)}{\left(x + -1\right) \cdot x}} \]
    2. *-un-lft-identity69.2%

      \[\leadsto \frac{\color{blue}{x} + \left(x + -1\right) \cdot \left(-1 - \frac{1}{x}\right)}{\left(x + -1\right) \cdot x} \]
  13. Applied egg-rr69.2%

    \[\leadsto \color{blue}{\frac{x + \left(x + -1\right) \cdot \left(-1 - \frac{1}{x}\right)}{\left(x + -1\right) \cdot x}} \]
  14. Taylor expanded in x around 0 73.1%

    \[\leadsto \frac{\color{blue}{\frac{1}{x}}}{\left(x + -1\right) \cdot x} \]
  15. Final simplification73.1%

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

Alternative 6: 67.8% accurate, 1.7× speedup?

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

\\
\frac{1}{x + -1} + \frac{-1}{x}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 68.9%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1}{x}} \]
  6. Add Preprocessing

Alternative 7: 67.6% accurate, 2.1× speedup?

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

\\
\frac{1}{x} + \frac{-1}{x}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 68.9%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1}{x}} \]
  6. Taylor expanded in x around inf 68.7%

    \[\leadsto \frac{1}{\color{blue}{x}} + \frac{-1}{x} \]
  7. Add Preprocessing

Alternative 8: 52.1% accurate, 3.0× speedup?

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

\\
\frac{\frac{1}{x}}{x}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 68.9%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1}{x}} \]
  6. Taylor expanded in x around inf 53.5%

    \[\leadsto \color{blue}{\frac{1}{{x}^{2}}} \]
  7. Step-by-step derivation
    1. unpow253.5%

      \[\leadsto \frac{1}{\color{blue}{x \cdot x}} \]
    2. associate-/l/51.8%

      \[\leadsto \color{blue}{\frac{\frac{1}{x}}{x}} \]
    3. rem-exp-log26.2%

      \[\leadsto \frac{\frac{1}{\color{blue}{e^{\log x}}}}{x} \]
    4. exp-neg26.2%

      \[\leadsto \frac{\color{blue}{e^{-\log x}}}{x} \]
    5. rem-exp-log26.2%

      \[\leadsto \frac{e^{-\log x}}{\color{blue}{e^{\log x}}} \]
    6. exp-diff26.2%

      \[\leadsto \color{blue}{e^{\left(-\log x\right) - \log x}} \]
    7. sub-neg26.2%

      \[\leadsto e^{\color{blue}{\left(-\log x\right) + \left(-\log x\right)}} \]
    8. neg-mul-126.2%

      \[\leadsto e^{\color{blue}{-1 \cdot \log x} + \left(-\log x\right)} \]
    9. neg-mul-126.2%

      \[\leadsto e^{-1 \cdot \log x + \color{blue}{-1 \cdot \log x}} \]
    10. distribute-rgt-out26.2%

      \[\leadsto e^{\color{blue}{\log x \cdot \left(-1 + -1\right)}} \]
    11. metadata-eval26.2%

      \[\leadsto e^{\log x \cdot \color{blue}{-2}} \]
    12. exp-to-pow51.8%

      \[\leadsto \color{blue}{{x}^{-2}} \]
  8. Simplified51.8%

    \[\leadsto \color{blue}{{x}^{-2}} \]
  9. Step-by-step derivation
    1. metadata-eval51.8%

      \[\leadsto {x}^{\color{blue}{\left(-1 - 1\right)}} \]
    2. pow-div51.8%

      \[\leadsto \color{blue}{\frac{{x}^{-1}}{{x}^{1}}} \]
    3. inv-pow51.8%

      \[\leadsto \frac{\color{blue}{\frac{1}{x}}}{{x}^{1}} \]
    4. pow151.8%

      \[\leadsto \frac{\frac{1}{x}}{\color{blue}{x}} \]
  10. Applied egg-rr51.8%

    \[\leadsto \color{blue}{\frac{\frac{1}{x}}{x}} \]
  11. Add Preprocessing

Alternative 9: 5.1% accurate, 5.0× speedup?

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

\\
\frac{-1}{x}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 68.9%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1}{x}} \]
  6. Taylor expanded in x around 0 5.2%

    \[\leadsto \color{blue}{\frac{-1}{x}} \]
  7. Add Preprocessing

Alternative 10: 5.0% accurate, 5.0× speedup?

\[\begin{array}{l} \\ \frac{-2}{x} \end{array} \]
(FPCore (x) :precision binary64 (/ -2.0 x))
double code(double x) {
	return -2.0 / x;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (-2.0d0) / x
end function
public static double code(double x) {
	return -2.0 / x;
}
def code(x):
	return -2.0 / x
function code(x)
	return Float64(-2.0 / x)
end
function tmp = code(x)
	tmp = -2.0 / x;
end
code[x_] := N[(-2.0 / x), $MachinePrecision]
\begin{array}{l}

\\
\frac{-2}{x}
\end{array}
Derivation
  1. Initial program 70.6%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg70.6%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-70.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub070.6%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg270.6%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+70.6%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative70.6%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg70.6%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac270.6%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-70.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub070.6%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified70.6%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around 0 5.1%

    \[\leadsto \color{blue}{\frac{-2}{x}} \]
  6. Add Preprocessing

Developer Target 1: 99.2% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \frac{2}{x \cdot \left(x \cdot x - 1\right)} \end{array} \]
(FPCore (x) :precision binary64 (/ 2.0 (* x (- (* x x) 1.0))))
double code(double x) {
	return 2.0 / (x * ((x * x) - 1.0));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 2.0d0 / (x * ((x * x) - 1.0d0))
end function
public static double code(double x) {
	return 2.0 / (x * ((x * x) - 1.0));
}
def code(x):
	return 2.0 / (x * ((x * x) - 1.0))
function code(x)
	return Float64(2.0 / Float64(x * Float64(Float64(x * x) - 1.0)))
end
function tmp = code(x)
	tmp = 2.0 / (x * ((x * x) - 1.0));
end
code[x_] := N[(2.0 / N[(x * N[(N[(x * x), $MachinePrecision] - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{x \cdot \left(x \cdot x - 1\right)}
\end{array}

Reproduce

?
herbie shell --seed 2024137 
(FPCore (x)
  :name "3frac (problem 3.3.3)"
  :precision binary64
  :pre (> (fabs x) 1.0)

  :alt
  (! :herbie-platform default (/ 2 (* x (- (* x x) 1))))

  (+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))