3frac (problem 3.3.3)

Percentage Accurate: 69.1% → 99.4%
Time: 10.2s
Alternatives: 10
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 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: 69.1% 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: 99.4% accurate, 0.8× speedup?

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

\\
\frac{\frac{2 + \frac{2 + \frac{2}{x \cdot x}}{x \cdot x}}{x \cdot x}}{x}
\end{array}
Derivation
  1. Initial program 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1 \cdot x + \left(x + -1\right) \cdot -2}{\color{blue}{\left(x + -1\right) \cdot x}}\right)\right) \]
    2. associate-/r*N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{\frac{1 \cdot x + \left(x + -1\right) \cdot -2}{x + -1}}{\color{blue}{x}}\right)\right) \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\left(\frac{1 \cdot x + \left(x + -1\right) \cdot -2}{x + -1}\right), \color{blue}{x}\right)\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(1 \cdot x + \left(x + -1\right) \cdot -2\right), \left(x + -1\right)\right), x\right)\right) \]
    5. *-lft-identityN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(x + \left(x + -1\right) \cdot -2\right), \left(x + -1\right)\right), x\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(x, \left(\left(x + -1\right) \cdot -2\right)\right), \left(x + -1\right)\right), x\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(x, \mathsf{*.f64}\left(\left(x + -1\right), -2\right)\right), \left(x + -1\right)\right), x\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(x, \mathsf{*.f64}\left(\mathsf{+.f64}\left(x, -1\right), -2\right)\right), \left(x + -1\right)\right), x\right)\right) \]
    9. +-lowering-+.f6471.0%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(x, \mathsf{*.f64}\left(\mathsf{+.f64}\left(x, -1\right), -2\right)\right), \mathsf{+.f64}\left(x, -1\right)\right), x\right)\right) \]
  6. Applied egg-rr71.0%

    \[\leadsto \frac{1}{1 + x} + \color{blue}{\frac{\frac{x + \left(x + -1\right) \cdot -2}{x + -1}}{x}} \]
  7. Taylor expanded in x around 0

    \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\color{blue}{\left(2 + -1 \cdot x\right)}, \mathsf{+.f64}\left(x, -1\right)\right), x\right)\right) \]
  8. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 + \left(\mathsf{neg}\left(x\right)\right)\right), \mathsf{+.f64}\left(x, -1\right)\right), x\right)\right) \]
    2. unsub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 - x\right), \mathsf{+.f64}\left(x, -1\right)\right), x\right)\right) \]
    3. --lowering--.f6471.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(2, x\right), \mathsf{+.f64}\left(x, -1\right)\right), x\right)\right) \]
  9. Simplified71.4%

    \[\leadsto \frac{1}{1 + x} + \frac{\frac{\color{blue}{2 - x}}{x + -1}}{x} \]
  10. Taylor expanded in x around -inf

    \[\leadsto \color{blue}{-1 \cdot \frac{-1 \cdot \frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{2}} - 2}{{x}^{3}}} \]
  11. Simplified99.0%

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

Alternative 2: 99.3% accurate, 1.0× speedup?

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

\\
\frac{\frac{1}{\frac{x \cdot x}{2 + \frac{2}{x \cdot x}}}}{x}
\end{array}
Derivation
  1. Initial program 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(2 + 2 \cdot \frac{1}{{x}^{2}}\right), \color{blue}{\left({x}^{3}\right)}\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(2 \cdot \frac{1}{{x}^{2}}\right)\right), \left({\color{blue}{x}}^{3}\right)\right) \]
    3. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2 \cdot 1}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    4. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left({x}^{2}\right)\right)\right), \left({x}^{3}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), \left({x}^{3}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left({x}^{3}\right)\right) \]
    8. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    12. *-lowering-*.f6497.1%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  7. Simplified97.1%

    \[\leadsto \color{blue}{\frac{2 + \frac{2}{x \cdot x}}{x \cdot \left(x \cdot x\right)}} \]
  8. Step-by-step derivation
    1. associate-/r*N/A

      \[\leadsto \frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{\color{blue}{x \cdot x}} \]
    2. associate-/r*N/A

      \[\leadsto \frac{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}}{\color{blue}{x}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}\right), \color{blue}{x}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(\frac{2 + \frac{2}{x \cdot x}}{x}\right), x\right), x\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 + \frac{2}{x \cdot x}\right), x\right), x\right), x\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{x \cdot x}\right)\right), x\right), x\right), x\right) \]
    7. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), x\right), x\right), x\right) \]
    8. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), x\right), x\right), x\right) \]
  9. Applied egg-rr98.8%

    \[\leadsto \color{blue}{\frac{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}}{x}} \]
  10. Step-by-step derivation
    1. associate-/l/N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{2 + \frac{2}{x \cdot x}}{x \cdot x}\right), x\right) \]
    2. clear-numN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{1}{\frac{x \cdot x}{2 + \frac{2}{x \cdot x}}}\right), x\right) \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(1, \left(\frac{x \cdot x}{2 + \frac{2}{x \cdot x}}\right)\right), x\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(1, \mathsf{/.f64}\left(\left(x \cdot x\right), \left(2 + \frac{2}{x \cdot x}\right)\right)\right), x\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(2 + \frac{2}{x \cdot x}\right)\right)\right), x\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(2, \left(\frac{2}{x \cdot x}\right)\right)\right)\right), x\right) \]
    7. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right)\right)\right), x\right) \]
    8. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right), x\right) \]
  11. Applied egg-rr98.8%

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

Alternative 3: 99.3% accurate, 1.2× speedup?

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

\\
\frac{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}}{x}
\end{array}
Derivation
  1. Initial program 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(2 + 2 \cdot \frac{1}{{x}^{2}}\right), \color{blue}{\left({x}^{3}\right)}\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(2 \cdot \frac{1}{{x}^{2}}\right)\right), \left({\color{blue}{x}}^{3}\right)\right) \]
    3. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2 \cdot 1}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    4. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left({x}^{2}\right)\right)\right), \left({x}^{3}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), \left({x}^{3}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left({x}^{3}\right)\right) \]
    8. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    12. *-lowering-*.f6497.1%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  7. Simplified97.1%

    \[\leadsto \color{blue}{\frac{2 + \frac{2}{x \cdot x}}{x \cdot \left(x \cdot x\right)}} \]
  8. Step-by-step derivation
    1. associate-/r*N/A

      \[\leadsto \frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{\color{blue}{x \cdot x}} \]
    2. associate-/r*N/A

      \[\leadsto \frac{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}}{\color{blue}{x}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}\right), \color{blue}{x}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(\frac{2 + \frac{2}{x \cdot x}}{x}\right), x\right), x\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 + \frac{2}{x \cdot x}\right), x\right), x\right), x\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{x \cdot x}\right)\right), x\right), x\right), x\right) \]
    7. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), x\right), x\right), x\right) \]
    8. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), x\right), x\right), x\right) \]
  9. Applied egg-rr98.8%

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

Alternative 4: 99.3% accurate, 1.2× speedup?

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

\\
\frac{\frac{2 + \frac{2}{x \cdot x}}{x \cdot x}}{x}
\end{array}
Derivation
  1. Initial program 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(2 + 2 \cdot \frac{1}{{x}^{2}}\right), \color{blue}{\left({x}^{3}\right)}\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(2 \cdot \frac{1}{{x}^{2}}\right)\right), \left({\color{blue}{x}}^{3}\right)\right) \]
    3. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2 \cdot 1}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    4. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left({x}^{2}\right)\right)\right), \left({x}^{3}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), \left({x}^{3}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left({x}^{3}\right)\right) \]
    8. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    12. *-lowering-*.f6497.1%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  7. Simplified97.1%

    \[\leadsto \color{blue}{\frac{2 + \frac{2}{x \cdot x}}{x \cdot \left(x \cdot x\right)}} \]
  8. Step-by-step derivation
    1. associate-*r*N/A

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

      \[\leadsto \frac{\frac{2 + \frac{2}{x \cdot x}}{x \cdot x}}{\color{blue}{x}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{2 + \frac{2}{x \cdot x}}{x \cdot x}\right), \color{blue}{x}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 + \frac{2}{x \cdot x}\right), \left(x \cdot x\right)\right), x\right) \]
    5. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{x \cdot x}\right)\right), \left(x \cdot x\right)\right), x\right) \]
    6. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), \left(x \cdot x\right)\right), x\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot x\right)\right), x\right) \]
    8. *-lowering-*.f6498.7%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, x\right)\right), x\right) \]
  9. Applied egg-rr98.7%

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

Alternative 5: 99.3% accurate, 1.2× speedup?

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

\\
\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x \cdot x}
\end{array}
Derivation
  1. Initial program 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(2 + 2 \cdot \frac{1}{{x}^{2}}\right), \color{blue}{\left({x}^{3}\right)}\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(2 \cdot \frac{1}{{x}^{2}}\right)\right), \left({\color{blue}{x}}^{3}\right)\right) \]
    3. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2 \cdot 1}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    4. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left({x}^{2}\right)\right)\right), \left({x}^{3}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), \left({x}^{3}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left({x}^{3}\right)\right) \]
    8. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    12. *-lowering-*.f6497.1%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  7. Simplified97.1%

    \[\leadsto \color{blue}{\frac{2 + \frac{2}{x \cdot x}}{x \cdot \left(x \cdot x\right)}} \]
  8. Step-by-step derivation
    1. associate-/r*N/A

      \[\leadsto \frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{\color{blue}{x \cdot x}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{2 + \frac{2}{x \cdot x}}{x}\right), \color{blue}{\left(x \cdot x\right)}\right) \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 + \frac{2}{x \cdot x}\right), x\right), \left(\color{blue}{x} \cdot x\right)\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{x \cdot x}\right)\right), x\right), \left(x \cdot x\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), x\right), \left(x \cdot x\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), x\right), \left(x \cdot x\right)\right) \]
    7. *-lowering-*.f6498.7%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), x\right), \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
  9. Applied egg-rr98.7%

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

Alternative 6: 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 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(2 + 2 \cdot \frac{1}{{x}^{2}}\right), \color{blue}{\left({x}^{3}\right)}\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(2 \cdot \frac{1}{{x}^{2}}\right)\right), \left({\color{blue}{x}}^{3}\right)\right) \]
    3. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2 \cdot 1}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    4. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left({x}^{2}\right)\right)\right), \left({x}^{3}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), \left({x}^{3}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left({x}^{3}\right)\right) \]
    8. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    12. *-lowering-*.f6497.1%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  7. Simplified97.1%

    \[\leadsto \color{blue}{\frac{2 + \frac{2}{x \cdot x}}{x \cdot \left(x \cdot x\right)}} \]
  8. Step-by-step derivation
    1. associate-/r*N/A

      \[\leadsto \frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{\color{blue}{x \cdot x}} \]
    2. associate-/r*N/A

      \[\leadsto \frac{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}}{\color{blue}{x}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}\right), \color{blue}{x}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(\frac{2 + \frac{2}{x \cdot x}}{x}\right), x\right), x\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 + \frac{2}{x \cdot x}\right), x\right), x\right), x\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{x \cdot x}\right)\right), x\right), x\right), x\right) \]
    7. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), x\right), x\right), x\right) \]
    8. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), x\right), x\right), x\right) \]
  9. Applied egg-rr98.8%

    \[\leadsto \color{blue}{\frac{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}}{x}} \]
  10. Taylor expanded in x around inf

    \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\color{blue}{\left(\frac{2}{x}\right)}, x\right), x\right) \]
  11. Step-by-step derivation
    1. /-lowering-/.f6498.1%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(2, x\right), x\right), x\right) \]
  12. Simplified98.1%

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

Alternative 7: 98.8% accurate, 2.1× speedup?

\[\begin{array}{l} \\ \frac{\frac{2}{x \cdot x}}{x} \end{array} \]
(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(2.0 / Float64(x * x)) / x)
end
function tmp = code(x)
	tmp = (2.0 / (x * x)) / x;
end
code[x_] := N[(N[(2.0 / N[(x * x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{2}{x \cdot x}}{x}
\end{array}
Derivation
  1. Initial program 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(2 + 2 \cdot \frac{1}{{x}^{2}}\right), \color{blue}{\left({x}^{3}\right)}\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(2 \cdot \frac{1}{{x}^{2}}\right)\right), \left({\color{blue}{x}}^{3}\right)\right) \]
    3. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2 \cdot 1}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    4. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left({x}^{2}\right)\right)\right), \left({x}^{3}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), \left({x}^{3}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left({x}^{3}\right)\right) \]
    8. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    12. *-lowering-*.f6497.1%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  7. Simplified97.1%

    \[\leadsto \color{blue}{\frac{2 + \frac{2}{x \cdot x}}{x \cdot \left(x \cdot x\right)}} \]
  8. Step-by-step derivation
    1. associate-/r*N/A

      \[\leadsto \frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{\color{blue}{x \cdot x}} \]
    2. associate-/r*N/A

      \[\leadsto \frac{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}}{\color{blue}{x}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}\right), \color{blue}{x}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(\frac{2 + \frac{2}{x \cdot x}}{x}\right), x\right), x\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 + \frac{2}{x \cdot x}\right), x\right), x\right), x\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{x \cdot x}\right)\right), x\right), x\right), x\right) \]
    7. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), x\right), x\right), x\right) \]
    8. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), x\right), x\right), x\right) \]
  9. Applied egg-rr98.8%

    \[\leadsto \color{blue}{\frac{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x}}{x}} \]
  10. Taylor expanded in x around inf

    \[\leadsto \mathsf{/.f64}\left(\color{blue}{\left(\frac{2}{{x}^{2}}\right)}, x\right) \]
  11. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(2, \left({x}^{2}\right)\right), x\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(2, \left(x \cdot x\right)\right), x\right) \]
    3. *-lowering-*.f6498.0%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right), x\right) \]
  12. Simplified98.0%

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

Alternative 8: 98.8% accurate, 2.1× speedup?

\[\begin{array}{l} \\ \frac{\frac{2}{x}}{x \cdot x} \end{array} \]
(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(2.0 / x) / Float64(x * x))
end
function tmp = code(x)
	tmp = (2.0 / x) / (x * x);
end
code[x_] := N[(N[(2.0 / x), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{2}{x}}{x \cdot x}
\end{array}
Derivation
  1. Initial program 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{2 + 2 \cdot \frac{1}{{x}^{2}}}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(2 + 2 \cdot \frac{1}{{x}^{2}}\right), \color{blue}{\left({x}^{3}\right)}\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(2 \cdot \frac{1}{{x}^{2}}\right)\right), \left({\color{blue}{x}}^{3}\right)\right) \]
    3. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2 \cdot 1}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    4. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{{x}^{2}}\right)\right), \left({x}^{3}\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left({x}^{2}\right)\right)\right), \left({x}^{3}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), \left({x}^{3}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left({x}^{3}\right)\right) \]
    8. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    12. *-lowering-*.f6497.1%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  7. Simplified97.1%

    \[\leadsto \color{blue}{\frac{2 + \frac{2}{x \cdot x}}{x \cdot \left(x \cdot x\right)}} \]
  8. Step-by-step derivation
    1. associate-/r*N/A

      \[\leadsto \frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{\color{blue}{x \cdot x}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{2 + \frac{2}{x \cdot x}}{x}\right), \color{blue}{\left(x \cdot x\right)}\right) \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(2 + \frac{2}{x \cdot x}\right), x\right), \left(\color{blue}{x} \cdot x\right)\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{2}{x \cdot x}\right)\right), x\right), \left(x \cdot x\right)\right) \]
    5. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \left(x \cdot x\right)\right)\right), x\right), \left(x \cdot x\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), x\right), \left(x \cdot x\right)\right) \]
    7. *-lowering-*.f6498.7%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right), x\right), \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
  9. Applied egg-rr98.7%

    \[\leadsto \color{blue}{\frac{\frac{2 + \frac{2}{x \cdot x}}{x}}{x \cdot x}} \]
  10. Taylor expanded in x around inf

    \[\leadsto \mathsf{/.f64}\left(\color{blue}{\left(\frac{2}{x}\right)}, \mathsf{*.f64}\left(x, x\right)\right) \]
  11. Step-by-step derivation
    1. /-lowering-/.f6498.0%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(2, x\right), \mathsf{*.f64}\left(\color{blue}{x}, x\right)\right) \]
  12. Simplified98.0%

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

Alternative 9: 98.1% accurate, 2.1× speedup?

\[\begin{array}{l} \\ \frac{2}{x \cdot \left(x \cdot x\right)} \end{array} \]
(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(2.0 / Float64(x * Float64(x * x)))
end
function tmp = code(x)
	tmp = 2.0 / (x * (x * x));
end
code[x_] := N[(2.0 / N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{x \cdot \left(x \cdot x\right)}
\end{array}
Derivation
  1. Initial program 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{2}{{x}^{3}}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left({x}^{3}\right)}\right) \]
    2. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    5. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    6. *-lowering-*.f6496.4%

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  7. Simplified96.4%

    \[\leadsto \color{blue}{\frac{2}{x \cdot \left(x \cdot x\right)}} \]
  8. Add Preprocessing

Alternative 10: 5.1% 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 71.4%

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \left(\frac{1}{x + 1} + \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right) + \frac{\color{blue}{1}}{x - 1} \]
    2. associate-+l+N/A

      \[\leadsto \frac{1}{x + 1} + \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)} \]
    3. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\frac{1}{x + 1}\right), \color{blue}{\left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)}\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + 1\right)\right), \left(\color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)} + \frac{1}{x - 1}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\left(\mathsf{neg}\left(\frac{2}{x}\right)\right) + \frac{1}{x - 1}\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \left(\frac{1}{x - 1} + \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\left(\frac{1}{x - 1}\right), \color{blue}{\left(\mathsf{neg}\left(\frac{2}{x}\right)\right)}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x - 1\right)\right), \left(\mathsf{neg}\left(\color{blue}{\frac{2}{x}}\right)\right)\right)\right) \]
    10. sub-negN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(x + \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, \left(\mathsf{neg}\left(1\right)\right)\right)\right), \left(\mathsf{neg}\left(\frac{2}{\color{blue}{x}}\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\mathsf{neg}\left(\frac{2}{x}\right)\right)\right)\right) \]
    13. distribute-neg-fracN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \left(\frac{\mathsf{neg}\left(2\right)}{\color{blue}{x}}\right)\right)\right) \]
    14. /-lowering-/.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(\left(\mathsf{neg}\left(2\right)\right), \color{blue}{x}\right)\right)\right) \]
    15. metadata-eval71.4%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, x\right)\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(x, -1\right)\right), \mathsf{/.f64}\left(-2, x\right)\right)\right) \]
  3. Simplified71.4%

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

    \[\leadsto \color{blue}{\frac{-2}{x}} \]
  6. Step-by-step derivation
    1. /-lowering-/.f645.1%

      \[\leadsto \mathsf{/.f64}\left(-2, \color{blue}{x}\right) \]
  7. Simplified5.1%

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

Developer Target 1: 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 2024155 
(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))))