3frac (problem 3.3.3)

Percentage Accurate: 69.3% → 99.7%
Time: 10.4s
Alternatives: 8
Speedup: 2.1×

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 8 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: 69.3% 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?

\[\begin{array}{l} \\ \left(\left({x}^{-4} + 1\right) \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right) \cdot {x}^{-3} \end{array} \]
(FPCore (x)
 :precision binary64
 (* (* (+ (pow x -4.0) 1.0) (fma 2.0 (pow x -2.0) 2.0)) (pow x -3.0)))
double code(double x) {
	return ((pow(x, -4.0) + 1.0) * fma(2.0, pow(x, -2.0), 2.0)) * pow(x, -3.0);
}
function code(x)
	return Float64(Float64(Float64((x ^ -4.0) + 1.0) * fma(2.0, (x ^ -2.0), 2.0)) * (x ^ -3.0))
end
code[x_] := N[(N[(N[(N[Power[x, -4.0], $MachinePrecision] + 1.0), $MachinePrecision] * N[(2.0 * N[Power[x, -2.0], $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision] * N[Power[x, -3.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left({x}^{-4} + 1\right) \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right) \cdot {x}^{-3}
\end{array}
Derivation
  1. Initial program 72.1%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative72.1%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg72.1%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac272.1%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub072.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified72.1%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around -inf 98.7%

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. mul-1-neg98.7%

      \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)}{{x}^{3}}} \]
    2. distribute-neg-frac98.7%

      \[\leadsto \color{blue}{\frac{-\left(-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)\right)}{{x}^{3}}} \]
  7. Simplified98.7%

    \[\leadsto \color{blue}{\frac{\frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}} + \left(2 + \frac{2}{{x}^{2}}\right)}{{x}^{3}}} \]
  8. Step-by-step derivation
    1. div-inv98.7%

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

      \[\leadsto \left(\color{blue}{\left(2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{4}}} + \left(2 + \frac{2}{{x}^{2}}\right)\right) \cdot \frac{1}{{x}^{3}} \]
    3. fma-define98.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(2 + \frac{2}{{x}^{2}}, \frac{1}{{x}^{4}}, 2 + \frac{2}{{x}^{2}}\right)} \cdot \frac{1}{{x}^{3}} \]
    4. +-commutative98.7%

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

      \[\leadsto \mathsf{fma}\left(\color{blue}{2 \cdot \frac{1}{{x}^{2}}} + 2, \frac{1}{{x}^{4}}, 2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{3}} \]
    6. fma-define98.7%

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, 2\right)}, \frac{1}{{x}^{4}}, 2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{3}} \]
    7. pow-flip98.7%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, 2\right), \frac{1}{{x}^{4}}, 2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{3}} \]
    8. metadata-eval98.7%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{\color{blue}{-2}}, 2\right), \frac{1}{{x}^{4}}, 2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{3}} \]
    9. pow-flip98.7%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), \color{blue}{{x}^{\left(-4\right)}}, 2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{3}} \]
    10. metadata-eval98.7%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), {x}^{\color{blue}{-4}}, 2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{3}} \]
    11. +-commutative98.7%

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

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), {x}^{-4}, \color{blue}{2 \cdot \frac{1}{{x}^{2}}} + 2\right) \cdot \frac{1}{{x}^{3}} \]
    13. fma-define98.7%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), {x}^{-4}, \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, 2\right)}\right) \cdot \frac{1}{{x}^{3}} \]
    14. pow-flip98.7%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), {x}^{-4}, \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, 2\right)\right) \cdot \frac{1}{{x}^{3}} \]
    15. metadata-eval98.7%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), {x}^{-4}, \mathsf{fma}\left(2, {x}^{\color{blue}{-2}}, 2\right)\right) \cdot \frac{1}{{x}^{3}} \]
    16. pow-flip99.5%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), {x}^{-4}, \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right) \cdot \color{blue}{{x}^{\left(-3\right)}} \]
    17. metadata-eval99.5%

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), {x}^{-4}, \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right) \cdot {x}^{\color{blue}{-3}} \]
  9. Applied egg-rr99.5%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right), {x}^{-4}, \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right) \cdot {x}^{-3}} \]
  10. Step-by-step derivation
    1. fma-undefine99.5%

      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{-4} + \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right)} \cdot {x}^{-3} \]
    2. *-commutative99.5%

      \[\leadsto \left(\color{blue}{{x}^{-4} \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)} + \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right) \cdot {x}^{-3} \]
    3. distribute-lft1-in99.5%

      \[\leadsto \color{blue}{\left(\left({x}^{-4} + 1\right) \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right)} \cdot {x}^{-3} \]
  11. Simplified99.5%

    \[\leadsto \color{blue}{\left(\left({x}^{-4} + 1\right) \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right) \cdot {x}^{-3}} \]
  12. Add Preprocessing

Alternative 2: 99.5% accurate, 0.0× speedup?

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

\\
\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{-3}
\end{array}
Derivation
  1. Initial program 72.1%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative72.1%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg72.1%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac272.1%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub072.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified72.1%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 98.5%

    \[\leadsto \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. associate-*r/98.5%

      \[\leadsto \frac{2 + \color{blue}{\frac{2 \cdot 1}{{x}^{2}}}}{{x}^{3}} \]
    2. metadata-eval98.5%

      \[\leadsto \frac{2 + \frac{\color{blue}{2}}{{x}^{2}}}{{x}^{3}} \]
  7. Simplified98.5%

    \[\leadsto \color{blue}{\frac{2 + \frac{2}{{x}^{2}}}{{x}^{3}}} \]
  8. Step-by-step derivation
    1. div-inv98.5%

      \[\leadsto \color{blue}{\left(2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{3}}} \]
    2. *-un-lft-identity98.5%

      \[\leadsto \color{blue}{\left(1 \cdot \left(2 + \frac{2}{{x}^{2}}\right)\right)} \cdot \frac{1}{{x}^{3}} \]
    3. pow-flip99.2%

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

      \[\leadsto \left(1 \cdot \left(2 + \frac{2}{{x}^{2}}\right)\right) \cdot {x}^{\color{blue}{-3}} \]
    5. +-commutative99.2%

      \[\leadsto \left(1 \cdot \color{blue}{\left(\frac{2}{{x}^{2}} + 2\right)}\right) \cdot {x}^{-3} \]
    6. *-un-lft-identity99.2%

      \[\leadsto \color{blue}{\left(\frac{2}{{x}^{2}} + 2\right)} \cdot {x}^{-3} \]
    7. div-inv99.2%

      \[\leadsto \left(\color{blue}{2 \cdot \frac{1}{{x}^{2}}} + 2\right) \cdot {x}^{-3} \]
    8. fma-define99.2%

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

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

      \[\leadsto \mathsf{fma}\left(2, {x}^{\color{blue}{-2}}, 2\right) \cdot {x}^{-3} \]
    11. *-un-lft-identity99.2%

      \[\leadsto \color{blue}{\left(1 \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)\right)} \cdot {x}^{-3} \]
    12. associate-*l*99.2%

      \[\leadsto \color{blue}{1 \cdot \left(\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{-3}\right)} \]
  9. Applied egg-rr99.2%

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

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

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

Alternative 3: 99.3% accurate, 0.1× speedup?

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

\\
\frac{1}{x} \cdot \frac{2 + \frac{2}{{x}^{2}}}{{x}^{2}}
\end{array}
Derivation
  1. Initial program 72.1%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative72.1%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg72.1%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac272.1%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub072.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified72.1%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around -inf 98.7%

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. mul-1-neg98.7%

      \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)}{{x}^{3}}} \]
    2. distribute-neg-frac98.7%

      \[\leadsto \color{blue}{\frac{-\left(-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)\right)}{{x}^{3}}} \]
  7. Simplified98.7%

    \[\leadsto \color{blue}{\frac{\frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}} + \left(2 + \frac{2}{{x}^{2}}\right)}{{x}^{3}}} \]
  8. Step-by-step derivation
    1. +-commutative98.7%

      \[\leadsto \frac{\color{blue}{\left(2 + \frac{2}{{x}^{2}}\right) + \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}}}{{x}^{3}} \]
    2. *-un-lft-identity98.7%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(2 + \frac{2}{{x}^{2}}\right)} + \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}}{{x}^{3}} \]
    3. fma-define98.7%

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(1, 2 + \frac{2}{{x}^{2}}, \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}\right)}}{{x}^{3}} \]
    4. +-commutative98.7%

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

      \[\leadsto \frac{\mathsf{fma}\left(1, \color{blue}{2 \cdot \frac{1}{{x}^{2}}} + 2, \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}\right)}{{x}^{3}} \]
    6. fma-define98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, 2\right)}, \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}\right)}{{x}^{3}} \]
    7. pow-flip98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, 2\right), \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}\right)}{{x}^{3}} \]
    8. metadata-eval98.7%

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

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \color{blue}{\left(2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{4}}}\right)}{{x}^{3}} \]
    10. +-commutative98.7%

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

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \left(\color{blue}{2 \cdot \frac{1}{{x}^{2}}} + 2\right) \cdot \frac{1}{{x}^{4}}\right)}{{x}^{3}} \]
    12. fma-define98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, 2\right)} \cdot \frac{1}{{x}^{4}}\right)}{{x}^{3}} \]
    13. pow-flip98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, 2\right) \cdot \frac{1}{{x}^{4}}\right)}{{x}^{3}} \]
    14. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, {x}^{\color{blue}{-2}}, 2\right) \cdot \frac{1}{{x}^{4}}\right)}{{x}^{3}} \]
    15. pow-flip98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \color{blue}{{x}^{\left(-4\right)}}\right)}{{x}^{3}} \]
    16. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{\color{blue}{-4}}\right)}{{x}^{3}} \]
  9. Applied egg-rr98.7%

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{-4}\right)}}{{x}^{3}} \]
  10. Step-by-step derivation
    1. fma-undefine98.7%

      \[\leadsto \frac{\color{blue}{1 \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right) + \mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{-4}}}{{x}^{3}} \]
    2. *-commutative98.7%

      \[\leadsto \frac{1 \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right) + \color{blue}{{x}^{-4} \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)}}{{x}^{3}} \]
    3. distribute-rgt-out98.7%

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)}}{{x}^{3}} \]
  11. Simplified98.7%

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)}}{{x}^{3}} \]
  12. Step-by-step derivation
    1. *-un-lft-identity98.7%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)\right)}}{{x}^{3}} \]
    2. cube-mult98.7%

      \[\leadsto \frac{1 \cdot \left(\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)\right)}{\color{blue}{x \cdot \left(x \cdot x\right)}} \]
    3. unpow298.7%

      \[\leadsto \frac{1 \cdot \left(\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)\right)}{x \cdot \color{blue}{{x}^{2}}} \]
    4. times-frac99.3%

      \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)}{{x}^{2}}} \]
    5. +-commutative99.3%

      \[\leadsto \frac{1}{x} \cdot \frac{\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \color{blue}{\left({x}^{-4} + 1\right)}}{{x}^{2}} \]
    6. *-commutative99.3%

      \[\leadsto \frac{1}{x} \cdot \frac{\color{blue}{\left({x}^{-4} + 1\right) \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)}}{{x}^{2}} \]
  13. Applied egg-rr99.3%

    \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{\left({x}^{-4} + 1\right) \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)}{{x}^{2}}} \]
  14. Taylor expanded in x around inf 99.1%

    \[\leadsto \frac{1}{x} \cdot \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{2}}} \]
  15. Step-by-step derivation
    1. associate-*r/99.1%

      \[\leadsto \frac{1}{x} \cdot \frac{2 + \color{blue}{\frac{2 \cdot 1}{{x}^{2}}}}{{x}^{2}} \]
    2. metadata-eval99.1%

      \[\leadsto \frac{1}{x} \cdot \frac{2 + \frac{\color{blue}{2}}{{x}^{2}}}{{x}^{2}} \]
  16. Simplified99.1%

    \[\leadsto \frac{1}{x} \cdot \color{blue}{\frac{2 + \frac{2}{{x}^{2}}}{{x}^{2}}} \]
  17. Add Preprocessing

Alternative 4: 98.7% accurate, 0.1× speedup?

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

\\
\frac{1}{x} \cdot \frac{2}{{x}^{2}}
\end{array}
Derivation
  1. Initial program 72.1%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative72.1%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg72.1%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac272.1%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub072.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified72.1%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around -inf 98.7%

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. mul-1-neg98.7%

      \[\leadsto \color{blue}{-\frac{-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)}{{x}^{3}}} \]
    2. distribute-neg-frac98.7%

      \[\leadsto \color{blue}{\frac{-\left(-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{4}} - \left(2 + 2 \cdot \frac{1}{{x}^{2}}\right)\right)}{{x}^{3}}} \]
  7. Simplified98.7%

    \[\leadsto \color{blue}{\frac{\frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}} + \left(2 + \frac{2}{{x}^{2}}\right)}{{x}^{3}}} \]
  8. Step-by-step derivation
    1. +-commutative98.7%

      \[\leadsto \frac{\color{blue}{\left(2 + \frac{2}{{x}^{2}}\right) + \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}}}{{x}^{3}} \]
    2. *-un-lft-identity98.7%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(2 + \frac{2}{{x}^{2}}\right)} + \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}}{{x}^{3}} \]
    3. fma-define98.7%

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(1, 2 + \frac{2}{{x}^{2}}, \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}\right)}}{{x}^{3}} \]
    4. +-commutative98.7%

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

      \[\leadsto \frac{\mathsf{fma}\left(1, \color{blue}{2 \cdot \frac{1}{{x}^{2}}} + 2, \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}\right)}{{x}^{3}} \]
    6. fma-define98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, 2\right)}, \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}\right)}{{x}^{3}} \]
    7. pow-flip98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, 2\right), \frac{2 + \frac{2}{{x}^{2}}}{{x}^{4}}\right)}{{x}^{3}} \]
    8. metadata-eval98.7%

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

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \color{blue}{\left(2 + \frac{2}{{x}^{2}}\right) \cdot \frac{1}{{x}^{4}}}\right)}{{x}^{3}} \]
    10. +-commutative98.7%

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

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \left(\color{blue}{2 \cdot \frac{1}{{x}^{2}}} + 2\right) \cdot \frac{1}{{x}^{4}}\right)}{{x}^{3}} \]
    12. fma-define98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \color{blue}{\mathsf{fma}\left(2, \frac{1}{{x}^{2}}, 2\right)} \cdot \frac{1}{{x}^{4}}\right)}{{x}^{3}} \]
    13. pow-flip98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, \color{blue}{{x}^{\left(-2\right)}}, 2\right) \cdot \frac{1}{{x}^{4}}\right)}{{x}^{3}} \]
    14. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, {x}^{\color{blue}{-2}}, 2\right) \cdot \frac{1}{{x}^{4}}\right)}{{x}^{3}} \]
    15. pow-flip98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \color{blue}{{x}^{\left(-4\right)}}\right)}{{x}^{3}} \]
    16. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{\color{blue}{-4}}\right)}{{x}^{3}} \]
  9. Applied egg-rr98.7%

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(1, \mathsf{fma}\left(2, {x}^{-2}, 2\right), \mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{-4}\right)}}{{x}^{3}} \]
  10. Step-by-step derivation
    1. fma-undefine98.7%

      \[\leadsto \frac{\color{blue}{1 \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right) + \mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot {x}^{-4}}}{{x}^{3}} \]
    2. *-commutative98.7%

      \[\leadsto \frac{1 \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right) + \color{blue}{{x}^{-4} \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)}}{{x}^{3}} \]
    3. distribute-rgt-out98.7%

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)}}{{x}^{3}} \]
  11. Simplified98.7%

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)}}{{x}^{3}} \]
  12. Step-by-step derivation
    1. *-un-lft-identity98.7%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)\right)}}{{x}^{3}} \]
    2. cube-mult98.7%

      \[\leadsto \frac{1 \cdot \left(\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)\right)}{\color{blue}{x \cdot \left(x \cdot x\right)}} \]
    3. unpow298.7%

      \[\leadsto \frac{1 \cdot \left(\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)\right)}{x \cdot \color{blue}{{x}^{2}}} \]
    4. times-frac99.3%

      \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \left(1 + {x}^{-4}\right)}{{x}^{2}}} \]
    5. +-commutative99.3%

      \[\leadsto \frac{1}{x} \cdot \frac{\mathsf{fma}\left(2, {x}^{-2}, 2\right) \cdot \color{blue}{\left({x}^{-4} + 1\right)}}{{x}^{2}} \]
    6. *-commutative99.3%

      \[\leadsto \frac{1}{x} \cdot \frac{\color{blue}{\left({x}^{-4} + 1\right) \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)}}{{x}^{2}} \]
  13. Applied egg-rr99.3%

    \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{\left({x}^{-4} + 1\right) \cdot \mathsf{fma}\left(2, {x}^{-2}, 2\right)}{{x}^{2}}} \]
  14. Taylor expanded in x around inf 98.7%

    \[\leadsto \frac{1}{x} \cdot \color{blue}{\frac{2}{{x}^{2}}} \]
  15. Add Preprocessing

Alternative 5: 67.9% accurate, 1.4× speedup?

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

\\
\frac{x + \left(-1 - x\right)}{x \cdot \left(1 - x\right)}
\end{array}
Derivation
  1. Initial program 72.1%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative72.1%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg72.1%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac272.1%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub072.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified72.1%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 70.6%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1}{x}} \]
  6. Step-by-step derivation
    1. frac-add70.6%

      \[\leadsto \color{blue}{\frac{1 \cdot x + \left(x + -1\right) \cdot -1}{\left(x + -1\right) \cdot x}} \]
    2. *-un-lft-identity70.6%

      \[\leadsto \frac{\color{blue}{x} + \left(x + -1\right) \cdot -1}{\left(x + -1\right) \cdot x} \]
  7. Applied egg-rr70.6%

    \[\leadsto \color{blue}{\frac{x + \left(x + -1\right) \cdot -1}{\left(x + -1\right) \cdot x}} \]
  8. Step-by-step derivation
    1. remove-double-neg70.6%

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

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

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

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

      \[\leadsto \frac{-\left(\color{blue}{-1 \cdot \left(x + -1\right)} + x\right)}{-\left(x + -1\right) \cdot x} \]
    6. neg-mul-170.6%

      \[\leadsto \frac{-\left(\color{blue}{\left(-\left(x + -1\right)\right)} + x\right)}{-\left(x + -1\right) \cdot x} \]
    7. distribute-neg-in70.6%

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

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

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

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

      \[\leadsto \frac{x + \left(-1 - x\right)}{-\color{blue}{x \cdot \left(x + -1\right)}} \]
    12. distribute-rgt-neg-out70.6%

      \[\leadsto \frac{x + \left(-1 - x\right)}{\color{blue}{x \cdot \left(-\left(x + -1\right)\right)}} \]
    13. distribute-neg-in70.6%

      \[\leadsto \frac{x + \left(-1 - x\right)}{x \cdot \color{blue}{\left(\left(-x\right) + \left(--1\right)\right)}} \]
    14. metadata-eval70.6%

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

      \[\leadsto \frac{x + \left(-1 - x\right)}{x \cdot \color{blue}{\left(1 + \left(-x\right)\right)}} \]
    16. unsub-neg70.6%

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

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

Alternative 6: 67.9% accurate, 1.7× speedup?

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

\\
\frac{-1}{1 - x} + \frac{-1}{x}
\end{array}
Derivation
  1. Initial program 72.1%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative72.1%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg72.1%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac272.1%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub072.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified72.1%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 70.6%

    \[\leadsto \frac{1}{x + -1} + \color{blue}{\frac{-1}{x}} \]
  6. Final simplification70.6%

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

Alternative 7: 98.8% accurate, 2.1× speedup?

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

\\
\frac{\frac{\frac{2}{x}}{x}}{x}
\end{array}
Derivation
  1. Initial program 72.1%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative72.1%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg72.1%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac272.1%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub072.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified72.1%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. inv-pow72.1%

      \[\leadsto \color{blue}{{\left(x + -1\right)}^{-1}} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right) \]
    2. add-sqr-sqrt24.4%

      \[\leadsto {\color{blue}{\left(\sqrt{x + -1} \cdot \sqrt{x + -1}\right)}}^{-1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right) \]
    3. unpow-prod-down16.8%

      \[\leadsto \color{blue}{{\left(\sqrt{x + -1}\right)}^{-1} \cdot {\left(\sqrt{x + -1}\right)}^{-1}} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right) \]
    4. fma-define4.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
    5. sub-neg4.0%

      \[\leadsto \mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \color{blue}{\frac{-2}{x} + \left(-\frac{1}{-1 - x}\right)}\right) \]
    6. distribute-neg-frac4.0%

      \[\leadsto \mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} + \color{blue}{\frac{-1}{-1 - x}}\right) \]
    7. metadata-eval4.0%

      \[\leadsto \mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} + \frac{\color{blue}{-1}}{-1 - x}\right) \]
  6. Applied egg-rr4.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} + \frac{-1}{-1 - x}\right)} \]
  7. Step-by-step derivation
    1. unpow-14.0%

      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{1}{\sqrt{x + -1}}}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} + \frac{-1}{-1 - x}\right) \]
    2. unpow-14.0%

      \[\leadsto \mathsf{fma}\left(\frac{1}{\sqrt{x + -1}}, \color{blue}{\frac{1}{\sqrt{x + -1}}}, \frac{-2}{x} + \frac{-1}{-1 - x}\right) \]
  8. Simplified4.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{x + -1}}, \frac{1}{\sqrt{x + -1}}, \frac{-2}{x} + \frac{-1}{-1 - x}\right)} \]
  9. Taylor expanded in x around -inf 0.0%

    \[\leadsto \color{blue}{-1 \cdot \frac{1 + \left(-1 \cdot \frac{-1 \cdot \frac{\frac{1}{{\left(\sqrt{-1}\right)}^{2}} - 1}{x} - \left(1 + \frac{1}{{\left(\sqrt{-1}\right)}^{2}}\right)}{x} + \frac{1}{{\left(\sqrt{-1}\right)}^{2}}\right)}{x}} \]
  10. Step-by-step derivation
    1. mul-1-neg0.0%

      \[\leadsto \color{blue}{-\frac{1 + \left(-1 \cdot \frac{-1 \cdot \frac{\frac{1}{{\left(\sqrt{-1}\right)}^{2}} - 1}{x} - \left(1 + \frac{1}{{\left(\sqrt{-1}\right)}^{2}}\right)}{x} + \frac{1}{{\left(\sqrt{-1}\right)}^{2}}\right)}{x}} \]
    2. distribute-neg-frac20.0%

      \[\leadsto \color{blue}{\frac{1 + \left(-1 \cdot \frac{-1 \cdot \frac{\frac{1}{{\left(\sqrt{-1}\right)}^{2}} - 1}{x} - \left(1 + \frac{1}{{\left(\sqrt{-1}\right)}^{2}}\right)}{x} + \frac{1}{{\left(\sqrt{-1}\right)}^{2}}\right)}{-x}} \]
  11. Simplified98.6%

    \[\leadsto \color{blue}{\frac{\frac{\frac{2}{x}}{-x} + 0}{-x}} \]
  12. Final simplification98.6%

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

Alternative 8: 67.7% accurate, 15.0× speedup?

\[\begin{array}{l} \\ 0 \end{array} \]
(FPCore (x) :precision binary64 0.0)
double code(double x) {
	return 0.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 0.0d0
end function
public static double code(double x) {
	return 0.0;
}
def code(x):
	return 0.0
function code(x)
	return 0.0
end
function tmp = code(x)
	tmp = 0.0;
end
code[x_] := 0.0
\begin{array}{l}

\\
0
\end{array}
Derivation
  1. Initial program 72.1%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. +-commutative72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)} \]
    2. associate-+r-72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) - \frac{2}{x}} \]
    3. sub-neg72.1%

      \[\leadsto \color{blue}{\left(\frac{1}{x - 1} + \frac{1}{x + 1}\right) + \left(-\frac{2}{x}\right)} \]
    4. remove-double-neg72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(-\left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    5. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{\left(0 - \left(-x\right)\right)} + 1}\right) + \left(-\frac{2}{x}\right) \]
    6. associate-+l-72.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{0 - \left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    7. neg-sub072.1%

      \[\leadsto \left(\frac{1}{x - 1} + \frac{1}{\color{blue}{-\left(\left(-x\right) - 1\right)}}\right) + \left(-\frac{2}{x}\right) \]
    8. distribute-neg-frac272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)}\right) + \left(-\frac{2}{x}\right) \]
    9. distribute-frac-neg272.1%

      \[\leadsto \left(\frac{1}{x - 1} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) + \color{blue}{\frac{2}{-x}} \]
    10. associate-+r+72.1%

      \[\leadsto \color{blue}{\frac{1}{x - 1} + \left(\left(-\frac{1}{\left(-x\right) - 1}\right) + \frac{2}{-x}\right)} \]
    11. +-commutative72.1%

      \[\leadsto \frac{1}{x - 1} + \color{blue}{\left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right)} \]
    12. remove-double-neg72.1%

      \[\leadsto \color{blue}{\left(-\left(-\frac{1}{x - 1}\right)\right)} + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    13. distribute-neg-frac272.1%

      \[\leadsto \left(-\color{blue}{\frac{1}{-\left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    14. sub0-neg72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{0 - \left(x - 1\right)}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    15. associate-+l-72.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(0 - x\right) + 1}}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
    16. neg-sub072.1%

      \[\leadsto \left(-\frac{1}{\color{blue}{\left(-x\right)} + 1}\right) + \left(\frac{2}{-x} + \left(-\frac{1}{\left(-x\right) - 1}\right)\right) \]
  3. Simplified72.1%

    \[\leadsto \color{blue}{\frac{1}{x + -1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. inv-pow72.1%

      \[\leadsto \color{blue}{{\left(x + -1\right)}^{-1}} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right) \]
    2. add-sqr-sqrt24.4%

      \[\leadsto {\color{blue}{\left(\sqrt{x + -1} \cdot \sqrt{x + -1}\right)}}^{-1} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right) \]
    3. unpow-prod-down16.8%

      \[\leadsto \color{blue}{{\left(\sqrt{x + -1}\right)}^{-1} \cdot {\left(\sqrt{x + -1}\right)}^{-1}} + \left(\frac{-2}{x} - \frac{1}{-1 - x}\right) \]
    4. fma-define4.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} - \frac{1}{-1 - x}\right)} \]
    5. sub-neg4.0%

      \[\leadsto \mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \color{blue}{\frac{-2}{x} + \left(-\frac{1}{-1 - x}\right)}\right) \]
    6. distribute-neg-frac4.0%

      \[\leadsto \mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} + \color{blue}{\frac{-1}{-1 - x}}\right) \]
    7. metadata-eval4.0%

      \[\leadsto \mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} + \frac{\color{blue}{-1}}{-1 - x}\right) \]
  6. Applied egg-rr4.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left({\left(\sqrt{x + -1}\right)}^{-1}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} + \frac{-1}{-1 - x}\right)} \]
  7. Step-by-step derivation
    1. unpow-14.0%

      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{1}{\sqrt{x + -1}}}, {\left(\sqrt{x + -1}\right)}^{-1}, \frac{-2}{x} + \frac{-1}{-1 - x}\right) \]
    2. unpow-14.0%

      \[\leadsto \mathsf{fma}\left(\frac{1}{\sqrt{x + -1}}, \color{blue}{\frac{1}{\sqrt{x + -1}}}, \frac{-2}{x} + \frac{-1}{-1 - x}\right) \]
  8. Simplified4.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{x + -1}}, \frac{1}{\sqrt{x + -1}}, \frac{-2}{x} + \frac{-1}{-1 - x}\right)} \]
  9. Taylor expanded in x around -inf 0.0%

    \[\leadsto \color{blue}{-1 \cdot \frac{1 + \frac{1}{{\left(\sqrt{-1}\right)}^{2}}}{x}} \]
  10. Step-by-step derivation
    1. associate-*r/0.0%

      \[\leadsto \color{blue}{\frac{-1 \cdot \left(1 + \frac{1}{{\left(\sqrt{-1}\right)}^{2}}\right)}{x}} \]
    2. distribute-rgt-in0.0%

      \[\leadsto \frac{\color{blue}{1 \cdot -1 + \frac{1}{{\left(\sqrt{-1}\right)}^{2}} \cdot -1}}{x} \]
    3. metadata-eval0.0%

      \[\leadsto \frac{\color{blue}{-1} + \frac{1}{{\left(\sqrt{-1}\right)}^{2}} \cdot -1}{x} \]
    4. unpow20.0%

      \[\leadsto \frac{-1 + \frac{1}{\color{blue}{\sqrt{-1} \cdot \sqrt{-1}}} \cdot -1}{x} \]
    5. rem-square-sqrt70.5%

      \[\leadsto \frac{-1 + \frac{1}{\color{blue}{-1}} \cdot -1}{x} \]
    6. metadata-eval70.5%

      \[\leadsto \frac{-1 + \color{blue}{-1} \cdot -1}{x} \]
    7. metadata-eval70.5%

      \[\leadsto \frac{-1 + \color{blue}{1}}{x} \]
    8. metadata-eval70.5%

      \[\leadsto \frac{\color{blue}{0}}{x} \]
    9. div070.5%

      \[\leadsto \color{blue}{0} \]
  11. Simplified70.5%

    \[\leadsto \color{blue}{0} \]
  12. Add Preprocessing

Developer target: 99.1% 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 2024106 
(FPCore (x)
  :name "3frac (problem 3.3.3)"
  :precision binary64
  :pre (> (fabs x) 1.0)

  :alt
  (/ 2.0 (* x (- (* x x) 1.0)))

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