2isqrt (example 3.6)

Percentage Accurate: 37.7% → 99.2%
Time: 10.8s
Alternatives: 10
Speedup: 2.0×

Specification

?
\[x > 1 \land x < 10^{+308}\]
\[\begin{array}{l} \\ \frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \end{array} \]
(FPCore (x) :precision binary64 (- (/ 1.0 (sqrt x)) (/ 1.0 (sqrt (+ x 1.0)))))
double code(double x) {
	return (1.0 / sqrt(x)) - (1.0 / sqrt((x + 1.0)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (1.0d0 / sqrt(x)) - (1.0d0 / sqrt((x + 1.0d0)))
end function
public static double code(double x) {
	return (1.0 / Math.sqrt(x)) - (1.0 / Math.sqrt((x + 1.0)));
}
def code(x):
	return (1.0 / math.sqrt(x)) - (1.0 / math.sqrt((x + 1.0)))
function code(x)
	return Float64(Float64(1.0 / sqrt(x)) - Float64(1.0 / sqrt(Float64(x + 1.0))))
end
function tmp = code(x)
	tmp = (1.0 / sqrt(x)) - (1.0 / sqrt((x + 1.0)));
end
code[x_] := N[(N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[(1.0 / N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{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: 37.7% accurate, 1.0× speedup?

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

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

Alternative 1: 99.2% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \frac{{\left(1 + x\right)}^{-0.5}}{x \cdot \left(2 + \frac{0.5 + \frac{-0.125 + \frac{0.0625}{x}}{x}}{x}\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  (pow (+ 1.0 x) -0.5)
  (* x (+ 2.0 (/ (+ 0.5 (/ (+ -0.125 (/ 0.0625 x)) x)) x)))))
double code(double x) {
	return pow((1.0 + x), -0.5) / (x * (2.0 + ((0.5 + ((-0.125 + (0.0625 / x)) / x)) / x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((1.0d0 + x) ** (-0.5d0)) / (x * (2.0d0 + ((0.5d0 + (((-0.125d0) + (0.0625d0 / x)) / x)) / x)))
end function
public static double code(double x) {
	return Math.pow((1.0 + x), -0.5) / (x * (2.0 + ((0.5 + ((-0.125 + (0.0625 / x)) / x)) / x)));
}
def code(x):
	return math.pow((1.0 + x), -0.5) / (x * (2.0 + ((0.5 + ((-0.125 + (0.0625 / x)) / x)) / x)))
function code(x)
	return Float64((Float64(1.0 + x) ^ -0.5) / Float64(x * Float64(2.0 + Float64(Float64(0.5 + Float64(Float64(-0.125 + Float64(0.0625 / x)) / x)) / x))))
end
function tmp = code(x)
	tmp = ((1.0 + x) ^ -0.5) / (x * (2.0 + ((0.5 + ((-0.125 + (0.0625 / x)) / x)) / x)));
end
code[x_] := N[(N[Power[N[(1.0 + x), $MachinePrecision], -0.5], $MachinePrecision] / N[(x * N[(2.0 + N[(N[(0.5 + N[(N[(-0.125 + N[(0.0625 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{{\left(1 + x\right)}^{-0.5}}{x \cdot \left(2 + \frac{0.5 + \frac{-0.125 + \frac{0.0625}{x}}{x}}{x}\right)}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

    \[\leadsto \color{blue}{\frac{\frac{\left(1 + x\right) - x}{x + \sqrt{x \cdot \left(1 + x\right)}}}{{\left(1 + x\right)}^{0.5}}} \]
  4. Step-by-step derivation
    1. associate-/l/N/A

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

      \[\leadsto \frac{1 + \left(x - x\right)}{\color{blue}{{\left(1 + x\right)}^{\frac{1}{2}}} \cdot \left(x + \sqrt{x \cdot \left(1 + x\right)}\right)} \]
    3. +-inversesN/A

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

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

      \[\leadsto \frac{\frac{1}{{\left(1 + x\right)}^{\frac{1}{2}}}}{\color{blue}{x + \sqrt{x \cdot \left(1 + x\right)}}} \]
    6. pow-flipN/A

      \[\leadsto \frac{{\left(1 + x\right)}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}}{\color{blue}{x} + \sqrt{x \cdot \left(1 + x\right)}} \]
    7. metadata-evalN/A

      \[\leadsto \frac{{\left(1 + x\right)}^{\frac{-1}{2}}}{x + \sqrt{x \cdot \left(1 + x\right)}} \]
    8. /-lowering-/.f64N/A

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

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

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

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

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

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{sqrt.f64}\left(\mathsf{*.f64}\left(x, \left(1 + x\right)\right)\right)\right)\right) \]
    14. +-lowering-+.f6481.6%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{sqrt.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, x\right)\right)\right)\right)\right) \]
  5. Applied egg-rr81.6%

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

    \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \color{blue}{\left(x \cdot \left(\left(2 + \left(\frac{1}{2} \cdot \frac{1}{x} + \frac{1}{16} \cdot \frac{1}{{x}^{3}}\right)\right) - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)}\right) \]
  7. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \color{blue}{\left(\left(2 + \left(\frac{1}{2} \cdot \frac{1}{x} + \frac{1}{16} \cdot \frac{1}{{x}^{3}}\right)\right) - \frac{\frac{1}{8}}{{x}^{2}}\right)}\right)\right) \]
    2. associate-+r+N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \frac{1}{16} \cdot \frac{1}{{x}^{3}}\right) - \frac{\color{blue}{\frac{1}{8}}}{{x}^{2}}\right)\right)\right) \]
    3. associate--l+N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \color{blue}{\left(\frac{1}{16} \cdot \frac{1}{{x}^{3}} - \frac{\frac{1}{8}}{{x}^{2}}\right)}\right)\right)\right) \]
    4. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{1}{16} \cdot 1}{{x}^{3}} - \frac{\color{blue}{\frac{1}{8}}}{{x}^{2}}\right)\right)\right)\right) \]
    5. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{1}{16}}{{x}^{3}} - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)\right)\right) \]
    6. unpow3N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{1}{16}}{\left(x \cdot x\right) \cdot x} - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)\right)\right) \]
    7. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{1}{16}}{{x}^{2} \cdot x} - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)\right)\right) \]
    8. associate-/r*N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\color{blue}{\frac{1}{8}}}{{x}^{2}}\right)\right)\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\frac{1}{8}}{x \cdot \color{blue}{x}}\right)\right)\right)\right) \]
    10. associate-/r*N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\frac{\frac{1}{8}}{x}}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\frac{\frac{1}{8} \cdot 1}{x}}{x}\right)\right)\right)\right) \]
    12. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\frac{1}{8} \cdot \frac{1}{x}}{x}\right)\right)\right)\right) \]
    13. div-subN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \frac{\frac{\frac{1}{16}}{{x}^{2}} - \frac{1}{8} \cdot \frac{1}{x}}{\color{blue}{x}}\right)\right)\right) \]
  8. Simplified99.0%

    \[\leadsto \frac{{\left(1 + x\right)}^{-0.5}}{\color{blue}{x \cdot \left(\left(2 + \frac{0.5}{x}\right) + \frac{\frac{-0.125 + \frac{0.0625}{x}}{x}}{x}\right)}} \]
  9. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \left(\left(\left(2 + \frac{\frac{1}{2}}{x}\right) + \frac{\frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}}{x}\right) \cdot \color{blue}{x}\right)\right) \]
    2. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\left(\left(2 + \frac{\frac{1}{2}}{x}\right) + \frac{\frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}}{x}\right), \color{blue}{x}\right)\right) \]
    3. associate-+l+N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\left(2 + \left(\frac{\frac{1}{2}}{x} + \frac{\frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}}{x}\right)\right), x\right)\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{\frac{1}{2}}{x} + \frac{\frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}}{x}\right)\right), x\right)\right) \]
    5. div-invN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{1}{2} \cdot \frac{1}{x} + \frac{\frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}}{x}\right)\right), x\right)\right) \]
    6. div-invN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{1}{2} \cdot \frac{1}{x} + \frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x} \cdot \frac{1}{x}\right)\right), x\right)\right) \]
    7. distribute-rgt-outN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{1}{x} \cdot \left(\frac{1}{2} + \frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}\right)\right)\right), x\right)\right) \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \left(\left(\frac{1}{2} + \frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}\right) \cdot \frac{1}{x}\right)\right), x\right)\right) \]
    9. un-div-invN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \left(\frac{\frac{1}{2} + \frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}}{x}\right)\right), x\right)\right) \]
    10. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\left(\frac{1}{2} + \frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}\right), x\right)\right), x\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \left(\frac{\frac{-1}{8} + \frac{\frac{1}{16}}{x}}{x}\right)\right), x\right)\right), x\right)\right) \]
    12. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\left(\frac{-1}{8} + \frac{\frac{1}{16}}{x}\right), x\right)\right), x\right)\right), x\right)\right) \]
    13. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{-1}{8}, \left(\frac{\frac{1}{16}}{x}\right)\right), x\right)\right), x\right)\right), x\right)\right) \]
    14. /-lowering-/.f6499.0%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(\mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{-1}{8}, \mathsf{/.f64}\left(\frac{1}{16}, x\right)\right), x\right)\right), x\right)\right), x\right)\right) \]
  10. Applied egg-rr99.0%

    \[\leadsto \frac{{\left(1 + x\right)}^{-0.5}}{\color{blue}{\left(2 + \frac{0.5 + \frac{-0.125 + \frac{0.0625}{x}}{x}}{x}\right) \cdot x}} \]
  11. Final simplification99.0%

    \[\leadsto \frac{{\left(1 + x\right)}^{-0.5}}{x \cdot \left(2 + \frac{0.5 + \frac{-0.125 + \frac{0.0625}{x}}{x}}{x}\right)} \]
  12. Add Preprocessing

Alternative 2: 99.1% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \frac{{\left(1 + x\right)}^{-0.5}}{x \cdot \left(2 + \frac{0.5 + \frac{-0.125}{x}}{x}\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ (pow (+ 1.0 x) -0.5) (* x (+ 2.0 (/ (+ 0.5 (/ -0.125 x)) x)))))
double code(double x) {
	return pow((1.0 + x), -0.5) / (x * (2.0 + ((0.5 + (-0.125 / x)) / x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((1.0d0 + x) ** (-0.5d0)) / (x * (2.0d0 + ((0.5d0 + ((-0.125d0) / x)) / x)))
end function
public static double code(double x) {
	return Math.pow((1.0 + x), -0.5) / (x * (2.0 + ((0.5 + (-0.125 / x)) / x)));
}
def code(x):
	return math.pow((1.0 + x), -0.5) / (x * (2.0 + ((0.5 + (-0.125 / x)) / x)))
function code(x)
	return Float64((Float64(1.0 + x) ^ -0.5) / Float64(x * Float64(2.0 + Float64(Float64(0.5 + Float64(-0.125 / x)) / x))))
end
function tmp = code(x)
	tmp = ((1.0 + x) ^ -0.5) / (x * (2.0 + ((0.5 + (-0.125 / x)) / x)));
end
code[x_] := N[(N[Power[N[(1.0 + x), $MachinePrecision], -0.5], $MachinePrecision] / N[(x * N[(2.0 + N[(N[(0.5 + N[(-0.125 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{{\left(1 + x\right)}^{-0.5}}{x \cdot \left(2 + \frac{0.5 + \frac{-0.125}{x}}{x}\right)}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

    \[\leadsto \color{blue}{\frac{\frac{\left(1 + x\right) - x}{x + \sqrt{x \cdot \left(1 + x\right)}}}{{\left(1 + x\right)}^{0.5}}} \]
  4. Step-by-step derivation
    1. associate-/l/N/A

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

      \[\leadsto \frac{1 + \left(x - x\right)}{\color{blue}{{\left(1 + x\right)}^{\frac{1}{2}}} \cdot \left(x + \sqrt{x \cdot \left(1 + x\right)}\right)} \]
    3. +-inversesN/A

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

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

      \[\leadsto \frac{\frac{1}{{\left(1 + x\right)}^{\frac{1}{2}}}}{\color{blue}{x + \sqrt{x \cdot \left(1 + x\right)}}} \]
    6. pow-flipN/A

      \[\leadsto \frac{{\left(1 + x\right)}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}}{\color{blue}{x} + \sqrt{x \cdot \left(1 + x\right)}} \]
    7. metadata-evalN/A

      \[\leadsto \frac{{\left(1 + x\right)}^{\frac{-1}{2}}}{x + \sqrt{x \cdot \left(1 + x\right)}} \]
    8. /-lowering-/.f64N/A

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

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

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

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

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

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{sqrt.f64}\left(\mathsf{*.f64}\left(x, \left(1 + x\right)\right)\right)\right)\right) \]
    14. +-lowering-+.f6481.6%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{sqrt.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, x\right)\right)\right)\right)\right) \]
  5. Applied egg-rr81.6%

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

    \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \color{blue}{\left(x \cdot \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)}\right) \]
  7. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \color{blue}{\left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) - \frac{\frac{1}{8}}{{x}^{2}}\right)}\right)\right) \]
    2. associate--l+N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{x} - \frac{\frac{1}{8}}{{x}^{2}}\right)}\right)\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \left(\frac{1}{2} \cdot \frac{1}{x} - \frac{\frac{1}{8}}{x \cdot \color{blue}{x}}\right)\right)\right)\right) \]
    4. associate-/r*N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \left(\frac{1}{2} \cdot \frac{1}{x} - \frac{\frac{\frac{1}{8}}{x}}{\color{blue}{x}}\right)\right)\right)\right) \]
    5. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \left(\frac{1}{2} \cdot \frac{1}{x} - \frac{\frac{\frac{1}{8} \cdot 1}{x}}{x}\right)\right)\right)\right) \]
    6. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \left(\frac{1}{2} \cdot \frac{1}{x} - \frac{\frac{1}{8} \cdot \frac{1}{x}}{x}\right)\right)\right)\right) \]
    7. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \left(\frac{\frac{1}{2} \cdot 1}{x} - \frac{\color{blue}{\frac{1}{8} \cdot \frac{1}{x}}}{x}\right)\right)\right)\right) \]
    8. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \left(\frac{\frac{1}{2}}{x} - \frac{\color{blue}{\frac{1}{8}} \cdot \frac{1}{x}}{x}\right)\right)\right)\right) \]
    9. div-subN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} - \frac{1}{8} \cdot \frac{1}{x}}{\color{blue}{x}}\right)\right)\right) \]
    10. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} - \frac{1}{x} \cdot \frac{1}{8}}{x}\right)\right)\right) \]
    11. cancel-sign-sub-invN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} + \left(\mathsf{neg}\left(\frac{1}{x}\right)\right) \cdot \frac{1}{8}}{x}\right)\right)\right) \]
    12. distribute-neg-frac2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} + \frac{1}{\mathsf{neg}\left(x\right)} \cdot \frac{1}{8}}{x}\right)\right)\right) \]
    13. mul-1-negN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} + \frac{1}{-1 \cdot x} \cdot \frac{1}{8}}{x}\right)\right)\right) \]
    14. rem-square-sqrtN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} + \frac{1}{\left(\sqrt{-1} \cdot \sqrt{-1}\right) \cdot x} \cdot \frac{1}{8}}{x}\right)\right)\right) \]
    15. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} + \frac{1}{{\left(\sqrt{-1}\right)}^{2} \cdot x} \cdot \frac{1}{8}}{x}\right)\right)\right) \]
    16. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} + \frac{1}{x \cdot {\left(\sqrt{-1}\right)}^{2}} \cdot \frac{1}{8}}{x}\right)\right)\right) \]
    17. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(2 + \frac{\frac{1}{2} + \frac{1}{8} \cdot \frac{1}{x \cdot {\left(\sqrt{-1}\right)}^{2}}}{x}\right)\right)\right) \]
  8. Simplified98.9%

    \[\leadsto \frac{{\left(1 + x\right)}^{-0.5}}{\color{blue}{x \cdot \left(2 + \frac{0.5 + \frac{-0.125}{x}}{x}\right)}} \]
  9. Add Preprocessing

Alternative 3: 98.9% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \frac{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}{\sqrt{1 + x}} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ (/ (+ 0.5 (/ (- -0.125 (/ -0.0625 x)) x)) x) (sqrt (+ 1.0 x))))
double code(double x) {
	return ((0.5 + ((-0.125 - (-0.0625 / x)) / x)) / x) / sqrt((1.0 + x));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((0.5d0 + (((-0.125d0) - ((-0.0625d0) / x)) / x)) / x) / sqrt((1.0d0 + x))
end function
public static double code(double x) {
	return ((0.5 + ((-0.125 - (-0.0625 / x)) / x)) / x) / Math.sqrt((1.0 + x));
}
def code(x):
	return ((0.5 + ((-0.125 - (-0.0625 / x)) / x)) / x) / math.sqrt((1.0 + x))
function code(x)
	return Float64(Float64(Float64(0.5 + Float64(Float64(-0.125 - Float64(-0.0625 / x)) / x)) / x) / sqrt(Float64(1.0 + x)))
end
function tmp = code(x)
	tmp = ((0.5 + ((-0.125 - (-0.0625 / x)) / x)) / x) / sqrt((1.0 + x));
end
code[x_] := N[(N[(N[(0.5 + N[(N[(-0.125 - N[(-0.0625 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}{\sqrt{1 + x}}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

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

    \[\leadsto \mathsf{/.f64}\left(\color{blue}{\left(\frac{\left(\frac{1}{2} + \frac{\frac{1}{16}}{{x}^{2}}\right) - \frac{1}{8} \cdot \frac{1}{x}}{x}\right)}, \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
  5. Simplified98.8%

    \[\leadsto \frac{\color{blue}{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}}{{\left(1 + x\right)}^{0.5}} \]
  6. Step-by-step derivation
    1. unpow1/2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\frac{-1}{8}, \mathsf{/.f64}\left(\frac{-1}{16}, x\right)\right), x\right)\right), x\right), \left(\sqrt{1 + x}\right)\right) \]
    2. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\frac{-1}{8}, \mathsf{/.f64}\left(\frac{-1}{16}, x\right)\right), x\right)\right), x\right), \mathsf{sqrt.f64}\left(\left(1 + x\right)\right)\right) \]
    3. +-lowering-+.f6498.8%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\frac{-1}{8}, \mathsf{/.f64}\left(\frac{-1}{16}, x\right)\right), x\right)\right), x\right), \mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, x\right)\right)\right) \]
  7. Applied egg-rr98.8%

    \[\leadsto \frac{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}{\color{blue}{\sqrt{1 + x}}} \]
  8. Add Preprocessing

Alternative 4: 98.8% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \frac{{\left(1 + x\right)}^{-0.5}}{x + \left(x + 0.5\right)} \end{array} \]
(FPCore (x) :precision binary64 (/ (pow (+ 1.0 x) -0.5) (+ x (+ x 0.5))))
double code(double x) {
	return pow((1.0 + x), -0.5) / (x + (x + 0.5));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((1.0d0 + x) ** (-0.5d0)) / (x + (x + 0.5d0))
end function
public static double code(double x) {
	return Math.pow((1.0 + x), -0.5) / (x + (x + 0.5));
}
def code(x):
	return math.pow((1.0 + x), -0.5) / (x + (x + 0.5))
function code(x)
	return Float64((Float64(1.0 + x) ^ -0.5) / Float64(x + Float64(x + 0.5)))
end
function tmp = code(x)
	tmp = ((1.0 + x) ^ -0.5) / (x + (x + 0.5));
end
code[x_] := N[(N[Power[N[(1.0 + x), $MachinePrecision], -0.5], $MachinePrecision] / N[(x + N[(x + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{{\left(1 + x\right)}^{-0.5}}{x + \left(x + 0.5\right)}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

    \[\leadsto \color{blue}{\frac{\frac{\left(1 + x\right) - x}{x + \sqrt{x \cdot \left(1 + x\right)}}}{{\left(1 + x\right)}^{0.5}}} \]
  4. Step-by-step derivation
    1. associate-/l/N/A

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

      \[\leadsto \frac{1 + \left(x - x\right)}{\color{blue}{{\left(1 + x\right)}^{\frac{1}{2}}} \cdot \left(x + \sqrt{x \cdot \left(1 + x\right)}\right)} \]
    3. +-inversesN/A

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

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

      \[\leadsto \frac{\frac{1}{{\left(1 + x\right)}^{\frac{1}{2}}}}{\color{blue}{x + \sqrt{x \cdot \left(1 + x\right)}}} \]
    6. pow-flipN/A

      \[\leadsto \frac{{\left(1 + x\right)}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}}{\color{blue}{x} + \sqrt{x \cdot \left(1 + x\right)}} \]
    7. metadata-evalN/A

      \[\leadsto \frac{{\left(1 + x\right)}^{\frac{-1}{2}}}{x + \sqrt{x \cdot \left(1 + x\right)}} \]
    8. /-lowering-/.f64N/A

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

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

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

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

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

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{sqrt.f64}\left(\mathsf{*.f64}\left(x, \left(1 + x\right)\right)\right)\right)\right) \]
    14. +-lowering-+.f6481.6%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{sqrt.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, x\right)\right)\right)\right)\right) \]
  5. Applied egg-rr81.6%

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

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

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \left(x \cdot \left(\frac{1}{2} \cdot \frac{1}{x} + \color{blue}{1}\right)\right)\right)\right) \]
    2. distribute-rgt-inN/A

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

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

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

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

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \left(\frac{1}{2} + x\right)\right)\right) \]
    7. +-lowering-+.f6498.5%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{2}, \color{blue}{x}\right)\right)\right) \]
  8. Simplified98.5%

    \[\leadsto \frac{{\left(1 + x\right)}^{-0.5}}{x + \color{blue}{\left(0.5 + x\right)}} \]
  9. Final simplification98.5%

    \[\leadsto \frac{{\left(1 + x\right)}^{-0.5}}{x + \left(x + 0.5\right)} \]
  10. Add Preprocessing

Alternative 5: 97.9% accurate, 2.0× speedup?

\[\begin{array}{l} \\ 0.5 \cdot {x}^{-1.5} \end{array} \]
(FPCore (x) :precision binary64 (* 0.5 (pow x -1.5)))
double code(double x) {
	return 0.5 * pow(x, -1.5);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 0.5d0 * (x ** (-1.5d0))
end function
public static double code(double x) {
	return 0.5 * Math.pow(x, -1.5);
}
def code(x):
	return 0.5 * math.pow(x, -1.5)
function code(x)
	return Float64(0.5 * (x ^ -1.5))
end
function tmp = code(x)
	tmp = 0.5 * (x ^ -1.5);
end
code[x_] := N[(0.5 * N[Power[x, -1.5], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.5 \cdot {x}^{-1.5}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Taylor expanded in x around inf

    \[\leadsto \color{blue}{\frac{\frac{1}{2} \cdot \left(\sqrt{\frac{1}{{x}^{3}}} \cdot \left(1 + \frac{1}{4} \cdot x\right)\right) - \left(\frac{-1}{2} \cdot \sqrt{x} + \frac{1}{2} \cdot \sqrt{\frac{1}{x}}\right)}{{x}^{2}}} \]
  4. Simplified80.2%

    \[\leadsto \color{blue}{\frac{\sqrt{\frac{1}{x \cdot \left(x \cdot x\right)}} \cdot \left(0.5 \cdot \left(1 + x \cdot 0.25\right)\right) + -0.5 \cdot \left(\sqrt{\frac{1}{x}} - \sqrt{x}\right)}{x \cdot x}} \]
  5. Taylor expanded in x around inf

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

      \[\leadsto \mathsf{/.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, \left(\sqrt{x}\right)\right), \mathsf{*.f64}\left(\color{blue}{x}, x\right)\right) \]
    2. sqrt-lowering-sqrt.f6478.9%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, \mathsf{sqrt.f64}\left(x\right)\right), \mathsf{*.f64}\left(x, x\right)\right) \]
  7. Simplified78.9%

    \[\leadsto \frac{\color{blue}{0.5 \cdot \sqrt{x}}}{x \cdot x} \]
  8. Step-by-step derivation
    1. associate-/l*N/A

      \[\leadsto \frac{1}{2} \cdot \color{blue}{\frac{\sqrt{x}}{x \cdot x}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{\sqrt{x}}{x \cdot x} \cdot \color{blue}{\frac{1}{2}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\left(\frac{\sqrt{x}}{x \cdot x}\right), \color{blue}{\frac{1}{2}}\right) \]
    4. pow1/2N/A

      \[\leadsto \mathsf{*.f64}\left(\left(\frac{{x}^{\frac{1}{2}}}{x \cdot x}\right), \frac{1}{2}\right) \]
    5. pow2N/A

      \[\leadsto \mathsf{*.f64}\left(\left(\frac{{x}^{\frac{1}{2}}}{{x}^{2}}\right), \frac{1}{2}\right) \]
    6. pow-divN/A

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

      \[\leadsto \mathsf{*.f64}\left(\mathsf{pow.f64}\left(x, \left(\frac{1}{2} - 2\right)\right), \frac{1}{2}\right) \]
    8. metadata-eval97.4%

      \[\leadsto \mathsf{*.f64}\left(\mathsf{pow.f64}\left(x, \frac{-3}{2}\right), \frac{1}{2}\right) \]
  9. Applied egg-rr97.4%

    \[\leadsto \color{blue}{{x}^{-1.5} \cdot 0.5} \]
  10. Final simplification97.4%

    \[\leadsto 0.5 \cdot {x}^{-1.5} \]
  11. Add Preprocessing

Alternative 6: 36.8% accurate, 12.3× speedup?

\[\begin{array}{l} \\ \frac{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}{1 + x \cdot 0.5} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ (/ (+ 0.5 (/ (- -0.125 (/ -0.0625 x)) x)) x) (+ 1.0 (* x 0.5))))
double code(double x) {
	return ((0.5 + ((-0.125 - (-0.0625 / x)) / x)) / x) / (1.0 + (x * 0.5));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((0.5d0 + (((-0.125d0) - ((-0.0625d0) / x)) / x)) / x) / (1.0d0 + (x * 0.5d0))
end function
public static double code(double x) {
	return ((0.5 + ((-0.125 - (-0.0625 / x)) / x)) / x) / (1.0 + (x * 0.5));
}
def code(x):
	return ((0.5 + ((-0.125 - (-0.0625 / x)) / x)) / x) / (1.0 + (x * 0.5))
function code(x)
	return Float64(Float64(Float64(0.5 + Float64(Float64(-0.125 - Float64(-0.0625 / x)) / x)) / x) / Float64(1.0 + Float64(x * 0.5)))
end
function tmp = code(x)
	tmp = ((0.5 + ((-0.125 - (-0.0625 / x)) / x)) / x) / (1.0 + (x * 0.5));
end
code[x_] := N[(N[(N[(0.5 + N[(N[(-0.125 - N[(-0.0625 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / N[(1.0 + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}{1 + x \cdot 0.5}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

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

    \[\leadsto \mathsf{/.f64}\left(\color{blue}{\left(\frac{\left(\frac{1}{2} + \frac{\frac{1}{16}}{{x}^{2}}\right) - \frac{1}{8} \cdot \frac{1}{x}}{x}\right)}, \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
  5. Simplified98.8%

    \[\leadsto \frac{\color{blue}{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}}{{\left(1 + x\right)}^{0.5}} \]
  6. Taylor expanded in x around 0

    \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\frac{-1}{8}, \mathsf{/.f64}\left(\frac{-1}{16}, x\right)\right), x\right)\right), x\right), \color{blue}{\left(1 + \frac{1}{2} \cdot x\right)}\right) \]
  7. Step-by-step derivation
    1. +-lowering-+.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\frac{-1}{8}, \mathsf{/.f64}\left(\frac{-1}{16}, x\right)\right), x\right)\right), x\right), \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{2} \cdot x\right)}\right)\right) \]
    2. *-lowering-*.f6435.9%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\frac{-1}{8}, \mathsf{/.f64}\left(\frac{-1}{16}, x\right)\right), x\right)\right), x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\frac{1}{2}, \color{blue}{x}\right)\right)\right) \]
  8. Simplified35.9%

    \[\leadsto \frac{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}{\color{blue}{1 + 0.5 \cdot x}} \]
  9. Final simplification35.9%

    \[\leadsto \frac{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}{1 + x \cdot 0.5} \]
  10. Add Preprocessing

Alternative 7: 36.8% accurate, 16.1× speedup?

\[\begin{array}{l} \\ \frac{\frac{0.5 + \frac{-0.125}{x}}{x}}{1 + x \cdot 0.5} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ (/ (+ 0.5 (/ -0.125 x)) x) (+ 1.0 (* x 0.5))))
double code(double x) {
	return ((0.5 + (-0.125 / x)) / x) / (1.0 + (x * 0.5));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((0.5d0 + ((-0.125d0) / x)) / x) / (1.0d0 + (x * 0.5d0))
end function
public static double code(double x) {
	return ((0.5 + (-0.125 / x)) / x) / (1.0 + (x * 0.5));
}
def code(x):
	return ((0.5 + (-0.125 / x)) / x) / (1.0 + (x * 0.5))
function code(x)
	return Float64(Float64(Float64(0.5 + Float64(-0.125 / x)) / x) / Float64(1.0 + Float64(x * 0.5)))
end
function tmp = code(x)
	tmp = ((0.5 + (-0.125 / x)) / x) / (1.0 + (x * 0.5));
end
code[x_] := N[(N[(N[(0.5 + N[(-0.125 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / N[(1.0 + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{0.5 + \frac{-0.125}{x}}{x}}{1 + x \cdot 0.5}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

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

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

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} - \frac{1}{x} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    2. cancel-sign-sub-invN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \left(\mathsf{neg}\left(\frac{1}{x}\right)\right) \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(\color{blue}{1}, x\right), \frac{1}{2}\right)\right) \]
    3. distribute-neg-frac2N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{\mathsf{neg}\left(x\right)} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    4. mul-1-negN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{-1 \cdot x} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    5. rem-square-sqrtN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{\left(\sqrt{-1} \cdot \sqrt{-1}\right) \cdot x} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{{\left(\sqrt{-1}\right)}^{2} \cdot x} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    7. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{x \cdot {\left(\sqrt{-1}\right)}^{2}} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{8} \cdot \frac{1}{x \cdot {\left(\sqrt{-1}\right)}^{2}}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(\frac{1}{2} + \frac{1}{8} \cdot \frac{1}{x \cdot {\left(\sqrt{-1}\right)}^{2}}\right), x\right), \mathsf{pow.f64}\left(\color{blue}{\mathsf{+.f64}\left(1, x\right)}, \frac{1}{2}\right)\right) \]
  6. Simplified98.4%

    \[\leadsto \frac{\color{blue}{\frac{0.5 + \frac{-0.125}{x}}{x}}}{{\left(1 + x\right)}^{0.5}} \]
  7. Taylor expanded in x around 0

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

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

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\frac{-1}{8}, x\right)\right), x\right), \mathsf{+.f64}\left(\left(\frac{1}{2} \cdot x\right), \color{blue}{1}\right)\right) \]
    3. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\frac{-1}{8}, x\right)\right), x\right), \mathsf{+.f64}\left(\left(x \cdot \frac{1}{2}\right), 1\right)\right) \]
    4. *-lowering-*.f6435.9%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{/.f64}\left(\frac{-1}{8}, x\right)\right), x\right), \mathsf{+.f64}\left(\mathsf{*.f64}\left(x, \frac{1}{2}\right), 1\right)\right) \]
  9. Simplified35.9%

    \[\leadsto \frac{\frac{0.5 + \frac{-0.125}{x}}{x}}{\color{blue}{x \cdot 0.5 + 1}} \]
  10. Final simplification35.9%

    \[\leadsto \frac{\frac{0.5 + \frac{-0.125}{x}}{x}}{1 + x \cdot 0.5} \]
  11. Add Preprocessing

Alternative 8: 35.7% accurate, 29.9× speedup?

\[\begin{array}{l} \\ \frac{0.0625}{x \cdot \left(x \cdot x\right)} \end{array} \]
(FPCore (x) :precision binary64 (/ 0.0625 (* x (* x x))))
double code(double x) {
	return 0.0625 / (x * (x * x));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 0.0625d0 / (x * (x * x))
end function
public static double code(double x) {
	return 0.0625 / (x * (x * x));
}
def code(x):
	return 0.0625 / (x * (x * x))
function code(x)
	return Float64(0.0625 / Float64(x * Float64(x * x)))
end
function tmp = code(x)
	tmp = 0.0625 / (x * (x * x));
end
code[x_] := N[(0.0625 / N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{0.0625}{x \cdot \left(x \cdot x\right)}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

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

    \[\leadsto \mathsf{/.f64}\left(\color{blue}{\left(\frac{\left(\frac{1}{2} + \frac{\frac{1}{16}}{{x}^{2}}\right) - \frac{1}{8} \cdot \frac{1}{x}}{x}\right)}, \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
  5. Simplified98.8%

    \[\leadsto \frac{\color{blue}{\frac{0.5 + \frac{-0.125 - \frac{-0.0625}{x}}{x}}{x}}}{{\left(1 + x\right)}^{0.5}} \]
  6. Taylor expanded in x around 0

    \[\leadsto \color{blue}{\frac{\frac{1}{16}}{{x}^{3}}} \]
  7. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\frac{1}{16}, \color{blue}{\left({x}^{3}\right)}\right) \]
    2. cube-multN/A

      \[\leadsto \mathsf{/.f64}\left(\frac{1}{16}, \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\frac{1}{16}, \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\frac{1}{16}, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    5. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\frac{1}{16}, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    6. *-lowering-*.f6434.7%

      \[\leadsto \mathsf{/.f64}\left(\frac{1}{16}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  8. Simplified34.7%

    \[\leadsto \color{blue}{\frac{0.0625}{x \cdot \left(x \cdot x\right)}} \]
  9. Add Preprocessing

Alternative 9: 34.1% accurate, 41.8× speedup?

\[\begin{array}{l} \\ \frac{-0.125}{x \cdot x} \end{array} \]
(FPCore (x) :precision binary64 (/ -0.125 (* x x)))
double code(double x) {
	return -0.125 / (x * x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (-0.125d0) / (x * x)
end function
public static double code(double x) {
	return -0.125 / (x * x);
}
def code(x):
	return -0.125 / (x * x)
function code(x)
	return Float64(-0.125 / Float64(x * x))
end
function tmp = code(x)
	tmp = -0.125 / (x * x);
end
code[x_] := N[(-0.125 / N[(x * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{-0.125}{x \cdot x}
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

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

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

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} - \frac{1}{x} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    2. cancel-sign-sub-invN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \left(\mathsf{neg}\left(\frac{1}{x}\right)\right) \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(\color{blue}{1}, x\right), \frac{1}{2}\right)\right) \]
    3. distribute-neg-frac2N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{\mathsf{neg}\left(x\right)} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    4. mul-1-negN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{-1 \cdot x} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    5. rem-square-sqrtN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{\left(\sqrt{-1} \cdot \sqrt{-1}\right) \cdot x} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{{\left(\sqrt{-1}\right)}^{2} \cdot x} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    7. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{x \cdot {\left(\sqrt{-1}\right)}^{2}} \cdot \frac{1}{8}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(\left(\frac{\frac{1}{2} + \frac{1}{8} \cdot \frac{1}{x \cdot {\left(\sqrt{-1}\right)}^{2}}}{x}\right), \mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{1}{2}\right)\right) \]
    9. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(\frac{1}{2} + \frac{1}{8} \cdot \frac{1}{x \cdot {\left(\sqrt{-1}\right)}^{2}}\right), x\right), \mathsf{pow.f64}\left(\color{blue}{\mathsf{+.f64}\left(1, x\right)}, \frac{1}{2}\right)\right) \]
  6. Simplified98.4%

    \[\leadsto \frac{\color{blue}{\frac{0.5 + \frac{-0.125}{x}}{x}}}{{\left(1 + x\right)}^{0.5}} \]
  7. Taylor expanded in x around 0

    \[\leadsto \color{blue}{\frac{\frac{-1}{8}}{{x}^{2}}} \]
  8. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\frac{-1}{8}, \color{blue}{\left({x}^{2}\right)}\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\frac{-1}{8}, \left(x \cdot \color{blue}{x}\right)\right) \]
    3. *-lowering-*.f6432.9%

      \[\leadsto \mathsf{/.f64}\left(\frac{-1}{8}, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
  9. Simplified32.9%

    \[\leadsto \color{blue}{\frac{-0.125}{x \cdot x}} \]
  10. Add Preprocessing

Alternative 10: 2.8% accurate, 41.8× speedup?

\[\begin{array}{l} \\ x \cdot \left(x \cdot 16\right) \end{array} \]
(FPCore (x) :precision binary64 (* x (* x 16.0)))
double code(double x) {
	return x * (x * 16.0);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x * (x * 16.0d0)
end function
public static double code(double x) {
	return x * (x * 16.0);
}
def code(x):
	return x * (x * 16.0)
function code(x)
	return Float64(x * Float64(x * 16.0))
end
function tmp = code(x)
	tmp = x * (x * 16.0);
end
code[x_] := N[(x * N[(x * 16.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot \left(x \cdot 16\right)
\end{array}
Derivation
  1. Initial program 37.0%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Applied egg-rr39.2%

    \[\leadsto \color{blue}{\frac{\frac{\left(1 + x\right) - x}{x + \sqrt{x \cdot \left(1 + x\right)}}}{{\left(1 + x\right)}^{0.5}}} \]
  4. Step-by-step derivation
    1. associate-/l/N/A

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

      \[\leadsto \frac{1 + \left(x - x\right)}{\color{blue}{{\left(1 + x\right)}^{\frac{1}{2}}} \cdot \left(x + \sqrt{x \cdot \left(1 + x\right)}\right)} \]
    3. +-inversesN/A

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

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

      \[\leadsto \frac{\frac{1}{{\left(1 + x\right)}^{\frac{1}{2}}}}{\color{blue}{x + \sqrt{x \cdot \left(1 + x\right)}}} \]
    6. pow-flipN/A

      \[\leadsto \frac{{\left(1 + x\right)}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}}{\color{blue}{x} + \sqrt{x \cdot \left(1 + x\right)}} \]
    7. metadata-evalN/A

      \[\leadsto \frac{{\left(1 + x\right)}^{\frac{-1}{2}}}{x + \sqrt{x \cdot \left(1 + x\right)}} \]
    8. /-lowering-/.f64N/A

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

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

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

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

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

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{sqrt.f64}\left(\mathsf{*.f64}\left(x, \left(1 + x\right)\right)\right)\right)\right) \]
    14. +-lowering-+.f6481.6%

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{+.f64}\left(x, \mathsf{sqrt.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, x\right)\right)\right)\right)\right) \]
  5. Applied egg-rr81.6%

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

    \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \color{blue}{\left(x \cdot \left(\left(2 + \left(\frac{1}{2} \cdot \frac{1}{x} + \frac{1}{16} \cdot \frac{1}{{x}^{3}}\right)\right) - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)}\right) \]
  7. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \color{blue}{\left(\left(2 + \left(\frac{1}{2} \cdot \frac{1}{x} + \frac{1}{16} \cdot \frac{1}{{x}^{3}}\right)\right) - \frac{\frac{1}{8}}{{x}^{2}}\right)}\right)\right) \]
    2. associate-+r+N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \frac{1}{16} \cdot \frac{1}{{x}^{3}}\right) - \frac{\color{blue}{\frac{1}{8}}}{{x}^{2}}\right)\right)\right) \]
    3. associate--l+N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \color{blue}{\left(\frac{1}{16} \cdot \frac{1}{{x}^{3}} - \frac{\frac{1}{8}}{{x}^{2}}\right)}\right)\right)\right) \]
    4. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{1}{16} \cdot 1}{{x}^{3}} - \frac{\color{blue}{\frac{1}{8}}}{{x}^{2}}\right)\right)\right)\right) \]
    5. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{1}{16}}{{x}^{3}} - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)\right)\right) \]
    6. unpow3N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{1}{16}}{\left(x \cdot x\right) \cdot x} - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)\right)\right) \]
    7. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{1}{16}}{{x}^{2} \cdot x} - \frac{\frac{1}{8}}{{x}^{2}}\right)\right)\right)\right) \]
    8. associate-/r*N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\color{blue}{\frac{1}{8}}}{{x}^{2}}\right)\right)\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\frac{1}{8}}{x \cdot \color{blue}{x}}\right)\right)\right)\right) \]
    10. associate-/r*N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\frac{\frac{1}{8}}{x}}{\color{blue}{x}}\right)\right)\right)\right) \]
    11. metadata-evalN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\frac{\frac{1}{8} \cdot 1}{x}}{x}\right)\right)\right)\right) \]
    12. associate-*r/N/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \left(\frac{\frac{\frac{1}{16}}{{x}^{2}}}{x} - \frac{\frac{1}{8} \cdot \frac{1}{x}}{x}\right)\right)\right)\right) \]
    13. div-subN/A

      \[\leadsto \mathsf{/.f64}\left(\mathsf{pow.f64}\left(\mathsf{+.f64}\left(1, x\right), \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) + \frac{\frac{\frac{1}{16}}{{x}^{2}} - \frac{1}{8} \cdot \frac{1}{x}}{\color{blue}{x}}\right)\right)\right) \]
  8. Simplified99.0%

    \[\leadsto \frac{{\left(1 + x\right)}^{-0.5}}{\color{blue}{x \cdot \left(\left(2 + \frac{0.5}{x}\right) + \frac{\frac{-0.125 + \frac{0.0625}{x}}{x}}{x}\right)}} \]
  9. Taylor expanded in x around 0

    \[\leadsto \color{blue}{16 \cdot {x}^{2}} \]
  10. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto {x}^{2} \cdot \color{blue}{16} \]
    2. unpow2N/A

      \[\leadsto \left(x \cdot x\right) \cdot 16 \]
    3. associate-*l*N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot 16\right)} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot 16\right)}\right) \]
    5. *-lowering-*.f643.0%

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{16}\right)\right) \]
  11. Simplified3.0%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot 16\right)} \]
  12. Add Preprocessing

Developer Target 1: 98.3% accurate, 1.0× speedup?

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

\\
\frac{1}{\left(x + 1\right) \cdot \sqrt{x} + x \cdot \sqrt{x + 1}}
\end{array}

Reproduce

?
herbie shell --seed 2024163 
(FPCore (x)
  :name "2isqrt (example 3.6)"
  :precision binary64
  :pre (and (> x 1.0) (< x 1e+308))

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

  (- (/ 1.0 (sqrt x)) (/ 1.0 (sqrt (+ x 1.0)))))