2cbrt (problem 3.3.4)

Percentage Accurate: 7.0% → 98.2%
Time: 12.3s
Alternatives: 7
Speedup: 1.0×

Specification

?
\[x > 1 \land x < 10^{+308}\]
\[\begin{array}{l} \\ \sqrt[3]{x + 1} - \sqrt[3]{x} \end{array} \]
(FPCore (x) :precision binary64 (- (cbrt (+ x 1.0)) (cbrt x)))
double code(double x) {
	return cbrt((x + 1.0)) - cbrt(x);
}
public static double code(double x) {
	return Math.cbrt((x + 1.0)) - Math.cbrt(x);
}
function code(x)
	return Float64(cbrt(Float64(x + 1.0)) - cbrt(x))
end
code[x_] := N[(N[Power[N[(x + 1.0), $MachinePrecision], 1/3], $MachinePrecision] - N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\sqrt[3]{x + 1} - \sqrt[3]{x}
\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 7 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: 7.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \sqrt[3]{x + 1} - \sqrt[3]{x} \end{array} \]
(FPCore (x) :precision binary64 (- (cbrt (+ x 1.0)) (cbrt x)))
double code(double x) {
	return cbrt((x + 1.0)) - cbrt(x);
}
public static double code(double x) {
	return Math.cbrt((x + 1.0)) - Math.cbrt(x);
}
function code(x)
	return Float64(cbrt(Float64(x + 1.0)) - cbrt(x))
end
code[x_] := N[(N[Power[N[(x + 1.0), $MachinePrecision], 1/3], $MachinePrecision] - N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\sqrt[3]{x + 1} - \sqrt[3]{x}
\end{array}

Alternative 1: 98.2% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \sqrt[3]{x \cdot 0.037037037037037035}}{x} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  (+
   (* (cbrt (/ 1.0 (pow x 2.0))) -0.1111111111111111)
   (cbrt (* x 0.037037037037037035)))
  x))
double code(double x) {
	return ((cbrt((1.0 / pow(x, 2.0))) * -0.1111111111111111) + cbrt((x * 0.037037037037037035))) / x;
}
public static double code(double x) {
	return ((Math.cbrt((1.0 / Math.pow(x, 2.0))) * -0.1111111111111111) + Math.cbrt((x * 0.037037037037037035))) / x;
}
function code(x)
	return Float64(Float64(Float64(cbrt(Float64(1.0 / (x ^ 2.0))) * -0.1111111111111111) + cbrt(Float64(x * 0.037037037037037035))) / x)
end
code[x_] := N[(N[(N[(N[Power[N[(1.0 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision] * -0.1111111111111111), $MachinePrecision] + N[Power[N[(x * 0.037037037037037035), $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}

\\
\frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \sqrt[3]{x \cdot 0.037037037037037035}}{x}
\end{array}
Derivation
  1. Initial program 6.4%

    \[\sqrt[3]{x + 1} - \sqrt[3]{x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. add-sqr-sqrt6.0%

      \[\leadsto \color{blue}{\sqrt{\sqrt[3]{x + 1}} \cdot \sqrt{\sqrt[3]{x + 1}}} - \sqrt[3]{x} \]
    2. add-sqr-sqrt6.3%

      \[\leadsto \sqrt{\sqrt[3]{x + 1}} \cdot \sqrt{\sqrt[3]{x + 1}} - \color{blue}{\sqrt{\sqrt[3]{x}} \cdot \sqrt{\sqrt[3]{x}}} \]
    3. difference-of-squares6.3%

      \[\leadsto \color{blue}{\left(\sqrt{\sqrt[3]{x + 1}} + \sqrt{\sqrt[3]{x}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right)} \]
    4. pow1/36.3%

      \[\leadsto \left(\sqrt{\color{blue}{{\left(x + 1\right)}^{0.3333333333333333}}} + \sqrt{\sqrt[3]{x}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    5. sqrt-pow16.3%

      \[\leadsto \left(\color{blue}{{\left(x + 1\right)}^{\left(\frac{0.3333333333333333}{2}\right)}} + \sqrt{\sqrt[3]{x}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    6. metadata-eval6.3%

      \[\leadsto \left({\left(x + 1\right)}^{\color{blue}{0.16666666666666666}} + \sqrt{\sqrt[3]{x}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    7. pow1/36.3%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + \sqrt{\color{blue}{{x}^{0.3333333333333333}}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    8. sqrt-pow16.3%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + \color{blue}{{x}^{\left(\frac{0.3333333333333333}{2}\right)}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    9. metadata-eval6.3%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{\color{blue}{0.16666666666666666}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    10. pow1/33.9%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left(\sqrt{\color{blue}{{\left(x + 1\right)}^{0.3333333333333333}}} - \sqrt{\sqrt[3]{x}}\right) \]
    11. sqrt-pow13.9%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left(\color{blue}{{\left(x + 1\right)}^{\left(\frac{0.3333333333333333}{2}\right)}} - \sqrt{\sqrt[3]{x}}\right) \]
    12. metadata-eval3.9%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{\color{blue}{0.16666666666666666}} - \sqrt{\sqrt[3]{x}}\right) \]
    13. pow1/36.2%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{0.16666666666666666} - \sqrt{\color{blue}{{x}^{0.3333333333333333}}}\right) \]
    14. sqrt-pow16.4%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{0.16666666666666666} - \color{blue}{{x}^{\left(\frac{0.3333333333333333}{2}\right)}}\right) \]
    15. metadata-eval6.4%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{0.16666666666666666} - {x}^{\color{blue}{0.16666666666666666}}\right) \]
  4. Applied egg-rr6.4%

    \[\leadsto \color{blue}{\left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{0.16666666666666666} - {x}^{0.16666666666666666}\right)} \]
  5. Taylor expanded in x around inf 98.5%

    \[\leadsto \color{blue}{\frac{-0.1388888888888889 \cdot \sqrt[3]{\frac{1}{{x}^{2}}} + \left(0.027777777777777776 \cdot \sqrt[3]{\frac{1}{{x}^{2}}} + 0.3333333333333333 \cdot \sqrt[3]{x}\right)}{x}} \]
  6. Step-by-step derivation
    1. associate-+r+98.5%

      \[\leadsto \frac{\color{blue}{\left(-0.1388888888888889 \cdot \sqrt[3]{\frac{1}{{x}^{2}}} + 0.027777777777777776 \cdot \sqrt[3]{\frac{1}{{x}^{2}}}\right) + 0.3333333333333333 \cdot \sqrt[3]{x}}}{x} \]
    2. distribute-rgt-out98.5%

      \[\leadsto \frac{\color{blue}{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot \left(-0.1388888888888889 + 0.027777777777777776\right)} + 0.3333333333333333 \cdot \sqrt[3]{x}}{x} \]
    3. metadata-eval98.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot \color{blue}{-0.1111111111111111} + 0.3333333333333333 \cdot \sqrt[3]{x}}{x} \]
    4. *-commutative98.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\sqrt[3]{x} \cdot 0.3333333333333333}}{x} \]
  7. Simplified98.5%

    \[\leadsto \color{blue}{\frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \sqrt[3]{x} \cdot 0.3333333333333333}{x}} \]
  8. Step-by-step derivation
    1. expm1-log1p-u92.7%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt[3]{x}\right)\right)} \cdot 0.3333333333333333}{x} \]
    2. expm1-undefine92.7%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\left(e^{\mathsf{log1p}\left(\sqrt[3]{x}\right)} - 1\right)} \cdot 0.3333333333333333}{x} \]
  9. Applied egg-rr92.7%

    \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\left(e^{\mathsf{log1p}\left(\sqrt[3]{x}\right)} - 1\right)} \cdot 0.3333333333333333}{x} \]
  10. Step-by-step derivation
    1. expm1-define92.7%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt[3]{x}\right)\right)} \cdot 0.3333333333333333}{x} \]
  11. Simplified92.7%

    \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt[3]{x}\right)\right)} \cdot 0.3333333333333333}{x} \]
  12. Step-by-step derivation
    1. expm1-log1p-u98.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\sqrt[3]{x}} \cdot 0.3333333333333333}{x} \]
    2. add-cbrt-cube98.4%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\sqrt[3]{\left(\left(\sqrt[3]{x} \cdot 0.3333333333333333\right) \cdot \left(\sqrt[3]{x} \cdot 0.3333333333333333\right)\right) \cdot \left(\sqrt[3]{x} \cdot 0.3333333333333333\right)}}}{x} \]
    3. pow1/391.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{{\left(\left(\left(\sqrt[3]{x} \cdot 0.3333333333333333\right) \cdot \left(\sqrt[3]{x} \cdot 0.3333333333333333\right)\right) \cdot \left(\sqrt[3]{x} \cdot 0.3333333333333333\right)\right)}^{0.3333333333333333}}}{x} \]
    4. pow391.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + {\color{blue}{\left({\left(\sqrt[3]{x} \cdot 0.3333333333333333\right)}^{3}\right)}}^{0.3333333333333333}}{x} \]
    5. unpow-prod-down91.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + {\color{blue}{\left({\left(\sqrt[3]{x}\right)}^{3} \cdot {0.3333333333333333}^{3}\right)}}^{0.3333333333333333}}{x} \]
    6. rem-cube-cbrt91.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + {\left(\color{blue}{x} \cdot {0.3333333333333333}^{3}\right)}^{0.3333333333333333}}{x} \]
    7. metadata-eval91.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + {\left(x \cdot \color{blue}{0.037037037037037035}\right)}^{0.3333333333333333}}{x} \]
  13. Applied egg-rr91.5%

    \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{{\left(x \cdot 0.037037037037037035\right)}^{0.3333333333333333}}}{x} \]
  14. Step-by-step derivation
    1. unpow1/398.7%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\sqrt[3]{x \cdot 0.037037037037037035}}}{x} \]
  15. Simplified98.7%

    \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\sqrt[3]{x \cdot 0.037037037037037035}}}{x} \]
  16. Add Preprocessing

Alternative 2: 98.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{-0.1111111111111111 \cdot {x}^{-0.6666666666666666} + \sqrt[3]{x} \cdot 0.3333333333333333}{x} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  (+
   (* -0.1111111111111111 (pow x -0.6666666666666666))
   (* (cbrt x) 0.3333333333333333))
  x))
double code(double x) {
	return ((-0.1111111111111111 * pow(x, -0.6666666666666666)) + (cbrt(x) * 0.3333333333333333)) / x;
}
public static double code(double x) {
	return ((-0.1111111111111111 * Math.pow(x, -0.6666666666666666)) + (Math.cbrt(x) * 0.3333333333333333)) / x;
}
function code(x)
	return Float64(Float64(Float64(-0.1111111111111111 * (x ^ -0.6666666666666666)) + Float64(cbrt(x) * 0.3333333333333333)) / x)
end
code[x_] := N[(N[(N[(-0.1111111111111111 * N[Power[x, -0.6666666666666666], $MachinePrecision]), $MachinePrecision] + N[(N[Power[x, 1/3], $MachinePrecision] * 0.3333333333333333), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}

\\
\frac{-0.1111111111111111 \cdot {x}^{-0.6666666666666666} + \sqrt[3]{x} \cdot 0.3333333333333333}{x}
\end{array}
Derivation
  1. Initial program 6.4%

    \[\sqrt[3]{x + 1} - \sqrt[3]{x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. add-sqr-sqrt6.0%

      \[\leadsto \color{blue}{\sqrt{\sqrt[3]{x + 1}} \cdot \sqrt{\sqrt[3]{x + 1}}} - \sqrt[3]{x} \]
    2. add-sqr-sqrt6.3%

      \[\leadsto \sqrt{\sqrt[3]{x + 1}} \cdot \sqrt{\sqrt[3]{x + 1}} - \color{blue}{\sqrt{\sqrt[3]{x}} \cdot \sqrt{\sqrt[3]{x}}} \]
    3. difference-of-squares6.3%

      \[\leadsto \color{blue}{\left(\sqrt{\sqrt[3]{x + 1}} + \sqrt{\sqrt[3]{x}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right)} \]
    4. pow1/36.3%

      \[\leadsto \left(\sqrt{\color{blue}{{\left(x + 1\right)}^{0.3333333333333333}}} + \sqrt{\sqrt[3]{x}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    5. sqrt-pow16.3%

      \[\leadsto \left(\color{blue}{{\left(x + 1\right)}^{\left(\frac{0.3333333333333333}{2}\right)}} + \sqrt{\sqrt[3]{x}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    6. metadata-eval6.3%

      \[\leadsto \left({\left(x + 1\right)}^{\color{blue}{0.16666666666666666}} + \sqrt{\sqrt[3]{x}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    7. pow1/36.3%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + \sqrt{\color{blue}{{x}^{0.3333333333333333}}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    8. sqrt-pow16.3%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + \color{blue}{{x}^{\left(\frac{0.3333333333333333}{2}\right)}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    9. metadata-eval6.3%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{\color{blue}{0.16666666666666666}}\right) \cdot \left(\sqrt{\sqrt[3]{x + 1}} - \sqrt{\sqrt[3]{x}}\right) \]
    10. pow1/33.9%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left(\sqrt{\color{blue}{{\left(x + 1\right)}^{0.3333333333333333}}} - \sqrt{\sqrt[3]{x}}\right) \]
    11. sqrt-pow13.9%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left(\color{blue}{{\left(x + 1\right)}^{\left(\frac{0.3333333333333333}{2}\right)}} - \sqrt{\sqrt[3]{x}}\right) \]
    12. metadata-eval3.9%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{\color{blue}{0.16666666666666666}} - \sqrt{\sqrt[3]{x}}\right) \]
    13. pow1/36.2%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{0.16666666666666666} - \sqrt{\color{blue}{{x}^{0.3333333333333333}}}\right) \]
    14. sqrt-pow16.4%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{0.16666666666666666} - \color{blue}{{x}^{\left(\frac{0.3333333333333333}{2}\right)}}\right) \]
    15. metadata-eval6.4%

      \[\leadsto \left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{0.16666666666666666} - {x}^{\color{blue}{0.16666666666666666}}\right) \]
  4. Applied egg-rr6.4%

    \[\leadsto \color{blue}{\left({\left(x + 1\right)}^{0.16666666666666666} + {x}^{0.16666666666666666}\right) \cdot \left({\left(x + 1\right)}^{0.16666666666666666} - {x}^{0.16666666666666666}\right)} \]
  5. Taylor expanded in x around inf 98.5%

    \[\leadsto \color{blue}{\frac{-0.1388888888888889 \cdot \sqrt[3]{\frac{1}{{x}^{2}}} + \left(0.027777777777777776 \cdot \sqrt[3]{\frac{1}{{x}^{2}}} + 0.3333333333333333 \cdot \sqrt[3]{x}\right)}{x}} \]
  6. Step-by-step derivation
    1. associate-+r+98.5%

      \[\leadsto \frac{\color{blue}{\left(-0.1388888888888889 \cdot \sqrt[3]{\frac{1}{{x}^{2}}} + 0.027777777777777776 \cdot \sqrt[3]{\frac{1}{{x}^{2}}}\right) + 0.3333333333333333 \cdot \sqrt[3]{x}}}{x} \]
    2. distribute-rgt-out98.5%

      \[\leadsto \frac{\color{blue}{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot \left(-0.1388888888888889 + 0.027777777777777776\right)} + 0.3333333333333333 \cdot \sqrt[3]{x}}{x} \]
    3. metadata-eval98.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot \color{blue}{-0.1111111111111111} + 0.3333333333333333 \cdot \sqrt[3]{x}}{x} \]
    4. *-commutative98.5%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \color{blue}{\sqrt[3]{x} \cdot 0.3333333333333333}}{x} \]
  7. Simplified98.5%

    \[\leadsto \color{blue}{\frac{\sqrt[3]{\frac{1}{{x}^{2}}} \cdot -0.1111111111111111 + \sqrt[3]{x} \cdot 0.3333333333333333}{x}} \]
  8. Step-by-step derivation
    1. pow1/398.5%

      \[\leadsto \frac{\color{blue}{{\left(\frac{1}{{x}^{2}}\right)}^{0.3333333333333333}} \cdot -0.1111111111111111 + \sqrt[3]{x} \cdot 0.3333333333333333}{x} \]
    2. pow-flip98.5%

      \[\leadsto \frac{{\color{blue}{\left({x}^{\left(-2\right)}\right)}}^{0.3333333333333333} \cdot -0.1111111111111111 + \sqrt[3]{x} \cdot 0.3333333333333333}{x} \]
    3. pow-pow98.5%

      \[\leadsto \frac{\color{blue}{{x}^{\left(\left(-2\right) \cdot 0.3333333333333333\right)}} \cdot -0.1111111111111111 + \sqrt[3]{x} \cdot 0.3333333333333333}{x} \]
    4. metadata-eval98.5%

      \[\leadsto \frac{{x}^{\left(\color{blue}{-2} \cdot 0.3333333333333333\right)} \cdot -0.1111111111111111 + \sqrt[3]{x} \cdot 0.3333333333333333}{x} \]
    5. metadata-eval98.5%

      \[\leadsto \frac{{x}^{\color{blue}{-0.6666666666666666}} \cdot -0.1111111111111111 + \sqrt[3]{x} \cdot 0.3333333333333333}{x} \]
  9. Applied egg-rr98.5%

    \[\leadsto \frac{\color{blue}{{x}^{-0.6666666666666666}} \cdot -0.1111111111111111 + \sqrt[3]{x} \cdot 0.3333333333333333}{x} \]
  10. Final simplification98.5%

    \[\leadsto \frac{-0.1111111111111111 \cdot {x}^{-0.6666666666666666} + \sqrt[3]{x} \cdot 0.3333333333333333}{x} \]
  11. Add Preprocessing

Alternative 3: 96.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{3 \cdot {\left(\sqrt[3]{x}\right)}^{2}} \end{array} \]
(FPCore (x) :precision binary64 (/ 1.0 (* 3.0 (pow (cbrt x) 2.0))))
double code(double x) {
	return 1.0 / (3.0 * pow(cbrt(x), 2.0));
}
public static double code(double x) {
	return 1.0 / (3.0 * Math.pow(Math.cbrt(x), 2.0));
}
function code(x)
	return Float64(1.0 / Float64(3.0 * (cbrt(x) ^ 2.0)))
end
code[x_] := N[(1.0 / N[(3.0 * N[Power[N[Power[x, 1/3], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{3 \cdot {\left(\sqrt[3]{x}\right)}^{2}}
\end{array}
Derivation
  1. Initial program 6.4%

    \[\sqrt[3]{x + 1} - \sqrt[3]{x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. flip3--6.6%

      \[\leadsto \color{blue}{\frac{{\left(\sqrt[3]{x + 1}\right)}^{3} - {\left(\sqrt[3]{x}\right)}^{3}}{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1} + \left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right)}} \]
    2. div-inv6.6%

      \[\leadsto \color{blue}{\left({\left(\sqrt[3]{x + 1}\right)}^{3} - {\left(\sqrt[3]{x}\right)}^{3}\right) \cdot \frac{1}{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1} + \left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right)}} \]
    3. rem-cube-cbrt6.3%

      \[\leadsto \left(\color{blue}{\left(x + 1\right)} - {\left(\sqrt[3]{x}\right)}^{3}\right) \cdot \frac{1}{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1} + \left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right)} \]
    4. rem-cube-cbrt8.6%

      \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1} + \left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right)} \]
    5. +-commutative8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\color{blue}{\left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right) + \sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}}} \]
    6. distribute-rgt-out8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\color{blue}{\sqrt[3]{x} \cdot \left(\sqrt[3]{x} + \sqrt[3]{x + 1}\right)} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}} \]
    7. +-commutative8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\sqrt[3]{x} \cdot \color{blue}{\left(\sqrt[3]{x + 1} + \sqrt[3]{x}\right)} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}} \]
    8. fma-define8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, \sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}\right)}} \]
    9. add-exp-log8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, \color{blue}{e^{\log \left(\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}\right)}}\right)} \]
  4. Applied egg-rr8.6%

    \[\leadsto \color{blue}{\left(\left(x + 1\right) - x\right) \cdot \frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)}} \]
  5. Step-by-step derivation
    1. associate-*r/8.6%

      \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot 1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)}} \]
    2. *-rgt-identity8.6%

      \[\leadsto \frac{\color{blue}{\left(x + 1\right) - x}}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    3. +-commutative8.6%

      \[\leadsto \frac{\color{blue}{\left(1 + x\right)} - x}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    4. associate--l+93.1%

      \[\leadsto \frac{\color{blue}{1 + \left(x - x\right)}}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    5. +-inverses93.1%

      \[\leadsto \frac{1 + \color{blue}{0}}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    6. metadata-eval93.1%

      \[\leadsto \frac{\color{blue}{1}}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    7. +-commutative93.1%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{\color{blue}{1 + x}} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    8. exp-prod92.2%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{1 + x} + \sqrt[3]{x}, \color{blue}{{\left(e^{0.6666666666666666}\right)}^{\left(\mathsf{log1p}\left(x\right)\right)}}\right)} \]
  6. Simplified92.2%

    \[\leadsto \color{blue}{\frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{1 + x} + \sqrt[3]{x}, {\left(e^{0.6666666666666666}\right)}^{\left(\mathsf{log1p}\left(x\right)\right)}\right)}} \]
  7. Taylor expanded in x around inf 22.9%

    \[\leadsto \frac{1}{\color{blue}{{x}^{2} \cdot \left(\sqrt[3]{\frac{1}{{x}^{4}}} + 2 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)}} \]
  8. Step-by-step derivation
    1. distribute-rgt1-in22.9%

      \[\leadsto \frac{1}{{x}^{2} \cdot \color{blue}{\left(\left(2 + 1\right) \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)}} \]
    2. metadata-eval22.9%

      \[\leadsto \frac{1}{{x}^{2} \cdot \left(\color{blue}{3} \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)} \]
  9. Simplified22.9%

    \[\leadsto \frac{1}{\color{blue}{{x}^{2} \cdot \left(3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)}} \]
  10. Step-by-step derivation
    1. /-rgt-identity22.9%

      \[\leadsto \frac{1}{\color{blue}{\frac{{x}^{2} \cdot \left(3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)}{1}}} \]
  11. Applied egg-rr23.6%

    \[\leadsto \frac{1}{\color{blue}{\frac{\left({x}^{2} \cdot 3\right) \cdot \sqrt[3]{{x}^{-4}}}{1}}} \]
  12. Simplified97.1%

    \[\leadsto \frac{1}{\color{blue}{3 \cdot {\left(\sqrt[3]{x}\right)}^{2}}} \]
  13. Add Preprocessing

Alternative 4: 96.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ 0.3333333333333333 \cdot {\left(\sqrt[3]{x}\right)}^{-2} \end{array} \]
(FPCore (x) :precision binary64 (* 0.3333333333333333 (pow (cbrt x) -2.0)))
double code(double x) {
	return 0.3333333333333333 * pow(cbrt(x), -2.0);
}
public static double code(double x) {
	return 0.3333333333333333 * Math.pow(Math.cbrt(x), -2.0);
}
function code(x)
	return Float64(0.3333333333333333 * (cbrt(x) ^ -2.0))
end
code[x_] := N[(0.3333333333333333 * N[Power[N[Power[x, 1/3], $MachinePrecision], -2.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.3333333333333333 \cdot {\left(\sqrt[3]{x}\right)}^{-2}
\end{array}
Derivation
  1. Initial program 6.4%

    \[\sqrt[3]{x + 1} - \sqrt[3]{x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. flip3--6.6%

      \[\leadsto \color{blue}{\frac{{\left(\sqrt[3]{x + 1}\right)}^{3} - {\left(\sqrt[3]{x}\right)}^{3}}{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1} + \left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right)}} \]
    2. div-inv6.6%

      \[\leadsto \color{blue}{\left({\left(\sqrt[3]{x + 1}\right)}^{3} - {\left(\sqrt[3]{x}\right)}^{3}\right) \cdot \frac{1}{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1} + \left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right)}} \]
    3. rem-cube-cbrt6.3%

      \[\leadsto \left(\color{blue}{\left(x + 1\right)} - {\left(\sqrt[3]{x}\right)}^{3}\right) \cdot \frac{1}{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1} + \left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right)} \]
    4. rem-cube-cbrt8.6%

      \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1} + \left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right)} \]
    5. +-commutative8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\color{blue}{\left(\sqrt[3]{x} \cdot \sqrt[3]{x} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x}\right) + \sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}}} \]
    6. distribute-rgt-out8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\color{blue}{\sqrt[3]{x} \cdot \left(\sqrt[3]{x} + \sqrt[3]{x + 1}\right)} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}} \]
    7. +-commutative8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\sqrt[3]{x} \cdot \color{blue}{\left(\sqrt[3]{x + 1} + \sqrt[3]{x}\right)} + \sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}} \]
    8. fma-define8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, \sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}\right)}} \]
    9. add-exp-log8.6%

      \[\leadsto \left(\left(x + 1\right) - x\right) \cdot \frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, \color{blue}{e^{\log \left(\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}\right)}}\right)} \]
  4. Applied egg-rr8.6%

    \[\leadsto \color{blue}{\left(\left(x + 1\right) - x\right) \cdot \frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)}} \]
  5. Step-by-step derivation
    1. associate-*r/8.6%

      \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot 1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)}} \]
    2. *-rgt-identity8.6%

      \[\leadsto \frac{\color{blue}{\left(x + 1\right) - x}}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    3. +-commutative8.6%

      \[\leadsto \frac{\color{blue}{\left(1 + x\right)} - x}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    4. associate--l+93.1%

      \[\leadsto \frac{\color{blue}{1 + \left(x - x\right)}}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    5. +-inverses93.1%

      \[\leadsto \frac{1 + \color{blue}{0}}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    6. metadata-eval93.1%

      \[\leadsto \frac{\color{blue}{1}}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{x + 1} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    7. +-commutative93.1%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{\color{blue}{1 + x}} + \sqrt[3]{x}, e^{0.6666666666666666 \cdot \mathsf{log1p}\left(x\right)}\right)} \]
    8. exp-prod92.2%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{1 + x} + \sqrt[3]{x}, \color{blue}{{\left(e^{0.6666666666666666}\right)}^{\left(\mathsf{log1p}\left(x\right)\right)}}\right)} \]
  6. Simplified92.2%

    \[\leadsto \color{blue}{\frac{1}{\mathsf{fma}\left(\sqrt[3]{x}, \sqrt[3]{1 + x} + \sqrt[3]{x}, {\left(e^{0.6666666666666666}\right)}^{\left(\mathsf{log1p}\left(x\right)\right)}\right)}} \]
  7. Taylor expanded in x around inf 22.9%

    \[\leadsto \frac{1}{\color{blue}{{x}^{2} \cdot \left(\sqrt[3]{\frac{1}{{x}^{4}}} + 2 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)}} \]
  8. Step-by-step derivation
    1. distribute-rgt1-in22.9%

      \[\leadsto \frac{1}{{x}^{2} \cdot \color{blue}{\left(\left(2 + 1\right) \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)}} \]
    2. metadata-eval22.9%

      \[\leadsto \frac{1}{{x}^{2} \cdot \left(\color{blue}{3} \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)} \]
  9. Simplified22.9%

    \[\leadsto \frac{1}{\color{blue}{{x}^{2} \cdot \left(3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)}} \]
  10. Step-by-step derivation
    1. associate-/r*22.8%

      \[\leadsto \color{blue}{\frac{\frac{1}{{x}^{2}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}}} \]
    2. add-cbrt-cube14.3%

      \[\leadsto \frac{\color{blue}{\sqrt[3]{\left(\frac{1}{{x}^{2}} \cdot \frac{1}{{x}^{2}}\right) \cdot \frac{1}{{x}^{2}}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    3. frac-times14.3%

      \[\leadsto \frac{\sqrt[3]{\color{blue}{\frac{1 \cdot 1}{{x}^{2} \cdot {x}^{2}}} \cdot \frac{1}{{x}^{2}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    4. metadata-eval14.3%

      \[\leadsto \frac{\sqrt[3]{\frac{\color{blue}{1}}{{x}^{2} \cdot {x}^{2}} \cdot \frac{1}{{x}^{2}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    5. pow-prod-up14.3%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{\color{blue}{{x}^{\left(2 + 2\right)}}} \cdot \frac{1}{{x}^{2}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    6. metadata-eval14.3%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{\color{blue}{4}}} \cdot \frac{1}{{x}^{2}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    7. cbrt-prod22.1%

      \[\leadsto \frac{\color{blue}{\sqrt[3]{\frac{1}{{x}^{4}}} \cdot \sqrt[3]{\frac{1}{{x}^{2}}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    8. *-un-lft-identity22.1%

      \[\leadsto \frac{\sqrt[3]{\frac{1}{{x}^{4}}} \cdot \sqrt[3]{\frac{1}{{x}^{2}}}}{\color{blue}{1 \cdot \left(3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}\right)}} \]
    9. times-frac22.1%

      \[\leadsto \color{blue}{\frac{\sqrt[3]{\frac{1}{{x}^{4}}}}{1} \cdot \frac{\sqrt[3]{\frac{1}{{x}^{2}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}}} \]
    10. pow-flip22.1%

      \[\leadsto \frac{\sqrt[3]{\color{blue}{{x}^{\left(-4\right)}}}}{1} \cdot \frac{\sqrt[3]{\frac{1}{{x}^{2}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    11. metadata-eval22.1%

      \[\leadsto \frac{\sqrt[3]{{x}^{\color{blue}{-4}}}}{1} \cdot \frac{\sqrt[3]{\frac{1}{{x}^{2}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    12. pow-flip22.1%

      \[\leadsto \frac{\sqrt[3]{{x}^{-4}}}{1} \cdot \frac{\sqrt[3]{\color{blue}{{x}^{\left(-2\right)}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
    13. metadata-eval22.1%

      \[\leadsto \frac{\sqrt[3]{{x}^{-4}}}{1} \cdot \frac{\sqrt[3]{{x}^{\color{blue}{-2}}}}{3 \cdot \sqrt[3]{\frac{1}{{x}^{4}}}} \]
  11. Applied egg-rr23.3%

    \[\leadsto \color{blue}{\frac{\sqrt[3]{{x}^{-4}}}{1} \cdot \frac{\sqrt[3]{{x}^{-2}}}{\sqrt[3]{{x}^{-4}} \cdot 3}} \]
  12. Step-by-step derivation
    1. /-rgt-identity23.3%

      \[\leadsto \color{blue}{\sqrt[3]{{x}^{-4}}} \cdot \frac{\sqrt[3]{{x}^{-2}}}{\sqrt[3]{{x}^{-4}} \cdot 3} \]
    2. associate-*r/23.3%

      \[\leadsto \color{blue}{\frac{\sqrt[3]{{x}^{-4}} \cdot \sqrt[3]{{x}^{-2}}}{\sqrt[3]{{x}^{-4}} \cdot 3}} \]
    3. times-frac23.3%

      \[\leadsto \color{blue}{\frac{\sqrt[3]{{x}^{-4}}}{\sqrt[3]{{x}^{-4}}} \cdot \frac{\sqrt[3]{{x}^{-2}}}{3}} \]
    4. *-inverses53.0%

      \[\leadsto \color{blue}{1} \cdot \frac{\sqrt[3]{{x}^{-2}}}{3} \]
    5. *-commutative53.0%

      \[\leadsto \color{blue}{\frac{\sqrt[3]{{x}^{-2}}}{3} \cdot 1} \]
    6. associate-*l/53.0%

      \[\leadsto \color{blue}{\frac{\sqrt[3]{{x}^{-2}} \cdot 1}{3}} \]
    7. associate-/l*52.8%

      \[\leadsto \color{blue}{\sqrt[3]{{x}^{-2}} \cdot \frac{1}{3}} \]
    8. unpow1/349.5%

      \[\leadsto \color{blue}{{\left({x}^{-2}\right)}^{0.3333333333333333}} \cdot \frac{1}{3} \]
    9. exp-to-pow49.7%

      \[\leadsto {\color{blue}{\left(e^{\log x \cdot -2}\right)}}^{0.3333333333333333} \cdot \frac{1}{3} \]
    10. *-commutative49.7%

      \[\leadsto {\left(e^{\color{blue}{-2 \cdot \log x}}\right)}^{0.3333333333333333} \cdot \frac{1}{3} \]
    11. exp-prod89.4%

      \[\leadsto \color{blue}{e^{\left(-2 \cdot \log x\right) \cdot 0.3333333333333333}} \cdot \frac{1}{3} \]
    12. associate-*l*89.4%

      \[\leadsto e^{\color{blue}{-2 \cdot \left(\log x \cdot 0.3333333333333333\right)}} \cdot \frac{1}{3} \]
    13. rem-log-exp89.4%

      \[\leadsto e^{-2 \cdot \color{blue}{\log \left(e^{\log x \cdot 0.3333333333333333}\right)}} \cdot \frac{1}{3} \]
    14. exp-to-pow89.7%

      \[\leadsto e^{-2 \cdot \log \color{blue}{\left({x}^{0.3333333333333333}\right)}} \cdot \frac{1}{3} \]
    15. unpow1/390.5%

      \[\leadsto e^{-2 \cdot \log \color{blue}{\left(\sqrt[3]{x}\right)}} \cdot \frac{1}{3} \]
    16. *-commutative90.5%

      \[\leadsto e^{\color{blue}{\log \left(\sqrt[3]{x}\right) \cdot -2}} \cdot \frac{1}{3} \]
    17. exp-to-pow97.0%

      \[\leadsto \color{blue}{{\left(\sqrt[3]{x}\right)}^{-2}} \cdot \frac{1}{3} \]
    18. metadata-eval97.0%

      \[\leadsto {\left(\sqrt[3]{x}\right)}^{-2} \cdot \color{blue}{0.3333333333333333} \]
  13. Simplified97.0%

    \[\leadsto \color{blue}{{\left(\sqrt[3]{x}\right)}^{-2} \cdot 0.3333333333333333} \]
  14. Final simplification97.0%

    \[\leadsto 0.3333333333333333 \cdot {\left(\sqrt[3]{x}\right)}^{-2} \]
  15. Add Preprocessing

Alternative 5: 51.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ 0.3333333333333333 \cdot \sqrt[3]{{x}^{-2}} \end{array} \]
(FPCore (x) :precision binary64 (* 0.3333333333333333 (cbrt (pow x -2.0))))
double code(double x) {
	return 0.3333333333333333 * cbrt(pow(x, -2.0));
}
public static double code(double x) {
	return 0.3333333333333333 * Math.cbrt(Math.pow(x, -2.0));
}
function code(x)
	return Float64(0.3333333333333333 * cbrt((x ^ -2.0)))
end
code[x_] := N[(0.3333333333333333 * N[Power[N[Power[x, -2.0], $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.3333333333333333 \cdot \sqrt[3]{{x}^{-2}}
\end{array}
Derivation
  1. Initial program 6.4%

    \[\sqrt[3]{x + 1} - \sqrt[3]{x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. pow1/37.4%

      \[\leadsto \sqrt[3]{x + 1} - \color{blue}{{x}^{0.3333333333333333}} \]
  4. Applied egg-rr7.4%

    \[\leadsto \sqrt[3]{x + 1} - \color{blue}{{x}^{0.3333333333333333}} \]
  5. Taylor expanded in x around inf 51.4%

    \[\leadsto \color{blue}{0.3333333333333333 \cdot \sqrt[3]{\frac{1}{{x}^{2}}}} \]
  6. Step-by-step derivation
    1. exp-to-pow48.7%

      \[\leadsto 0.3333333333333333 \cdot \sqrt[3]{\frac{1}{\color{blue}{e^{\log x \cdot 2}}}} \]
    2. *-commutative48.7%

      \[\leadsto 0.3333333333333333 \cdot \sqrt[3]{\frac{1}{e^{\color{blue}{2 \cdot \log x}}}} \]
    3. rec-exp50.1%

      \[\leadsto 0.3333333333333333 \cdot \sqrt[3]{\color{blue}{e^{-2 \cdot \log x}}} \]
    4. mul-1-neg50.1%

      \[\leadsto 0.3333333333333333 \cdot \sqrt[3]{e^{\color{blue}{-1 \cdot \left(2 \cdot \log x\right)}}} \]
    5. associate-*r*50.1%

      \[\leadsto 0.3333333333333333 \cdot \sqrt[3]{e^{\color{blue}{\left(-1 \cdot 2\right) \cdot \log x}}} \]
    6. metadata-eval50.1%

      \[\leadsto 0.3333333333333333 \cdot \sqrt[3]{e^{\color{blue}{-2} \cdot \log x}} \]
    7. *-commutative50.1%

      \[\leadsto 0.3333333333333333 \cdot \sqrt[3]{e^{\color{blue}{\log x \cdot -2}}} \]
    8. exp-to-pow52.8%

      \[\leadsto 0.3333333333333333 \cdot \sqrt[3]{\color{blue}{{x}^{-2}}} \]
  7. Simplified52.8%

    \[\leadsto \color{blue}{0.3333333333333333 \cdot \sqrt[3]{{x}^{-2}}} \]
  8. Add Preprocessing

Alternative 6: 5.4% accurate, 2.0× speedup?

\[\begin{array}{l} \\ 1 + \sqrt[3]{x} \end{array} \]
(FPCore (x) :precision binary64 (+ 1.0 (cbrt x)))
double code(double x) {
	return 1.0 + cbrt(x);
}
public static double code(double x) {
	return 1.0 + Math.cbrt(x);
}
function code(x)
	return Float64(1.0 + cbrt(x))
end
code[x_] := N[(1.0 + N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
1 + \sqrt[3]{x}
\end{array}
Derivation
  1. Initial program 6.4%

    \[\sqrt[3]{x + 1} - \sqrt[3]{x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0 1.8%

    \[\leadsto \color{blue}{1 - \sqrt[3]{x}} \]
  4. Step-by-step derivation
    1. sub-neg1.8%

      \[\leadsto \color{blue}{1 + \left(-\sqrt[3]{x}\right)} \]
    2. rem-square-sqrt0.0%

      \[\leadsto 1 + \color{blue}{\sqrt{-\sqrt[3]{x}} \cdot \sqrt{-\sqrt[3]{x}}} \]
    3. fabs-sqr0.0%

      \[\leadsto 1 + \color{blue}{\left|\sqrt{-\sqrt[3]{x}} \cdot \sqrt{-\sqrt[3]{x}}\right|} \]
    4. rem-square-sqrt5.3%

      \[\leadsto 1 + \left|\color{blue}{-\sqrt[3]{x}}\right| \]
    5. fabs-neg5.3%

      \[\leadsto 1 + \color{blue}{\left|\sqrt[3]{x}\right|} \]
    6. unpow1/35.3%

      \[\leadsto 1 + \left|\color{blue}{{x}^{0.3333333333333333}}\right| \]
    7. metadata-eval5.3%

      \[\leadsto 1 + \left|{x}^{\color{blue}{\left(2 \cdot 0.16666666666666666\right)}}\right| \]
    8. pow-sqr5.3%

      \[\leadsto 1 + \left|\color{blue}{{x}^{0.16666666666666666} \cdot {x}^{0.16666666666666666}}\right| \]
    9. fabs-sqr5.3%

      \[\leadsto 1 + \color{blue}{{x}^{0.16666666666666666} \cdot {x}^{0.16666666666666666}} \]
    10. pow-sqr5.3%

      \[\leadsto 1 + \color{blue}{{x}^{\left(2 \cdot 0.16666666666666666\right)}} \]
    11. metadata-eval5.3%

      \[\leadsto 1 + {x}^{\color{blue}{0.3333333333333333}} \]
    12. unpow1/35.3%

      \[\leadsto 1 + \color{blue}{\sqrt[3]{x}} \]
  5. Simplified5.3%

    \[\leadsto \color{blue}{1 + \sqrt[3]{x}} \]
  6. Add Preprocessing

Alternative 7: 4.1% accurate, 205.0× speedup?

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

\\
0
\end{array}
Derivation
  1. Initial program 6.4%

    \[\sqrt[3]{x + 1} - \sqrt[3]{x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around inf 4.1%

    \[\leadsto \color{blue}{\sqrt[3]{x}} - \sqrt[3]{x} \]
  4. Taylor expanded in x around 0 4.1%

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

Developer Target 1: 98.5% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt[3]{x + 1}\\ \frac{1}{\left(t\_0 \cdot t\_0 + \sqrt[3]{x} \cdot t\_0\right) + \sqrt[3]{x} \cdot \sqrt[3]{x}} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (cbrt (+ x 1.0))))
   (/ 1.0 (+ (+ (* t_0 t_0) (* (cbrt x) t_0)) (* (cbrt x) (cbrt x))))))
double code(double x) {
	double t_0 = cbrt((x + 1.0));
	return 1.0 / (((t_0 * t_0) + (cbrt(x) * t_0)) + (cbrt(x) * cbrt(x)));
}
public static double code(double x) {
	double t_0 = Math.cbrt((x + 1.0));
	return 1.0 / (((t_0 * t_0) + (Math.cbrt(x) * t_0)) + (Math.cbrt(x) * Math.cbrt(x)));
}
function code(x)
	t_0 = cbrt(Float64(x + 1.0))
	return Float64(1.0 / Float64(Float64(Float64(t_0 * t_0) + Float64(cbrt(x) * t_0)) + Float64(cbrt(x) * cbrt(x))))
end
code[x_] := Block[{t$95$0 = N[Power[N[(x + 1.0), $MachinePrecision], 1/3], $MachinePrecision]}, N[(1.0 / N[(N[(N[(t$95$0 * t$95$0), $MachinePrecision] + N[(N[Power[x, 1/3], $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision] + N[(N[Power[x, 1/3], $MachinePrecision] * N[Power[x, 1/3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt[3]{x + 1}\\
\frac{1}{\left(t\_0 \cdot t\_0 + \sqrt[3]{x} \cdot t\_0\right) + \sqrt[3]{x} \cdot \sqrt[3]{x}}
\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2024113 
(FPCore (x)
  :name "2cbrt (problem 3.3.4)"
  :precision binary64
  :pre (and (> x 1.0) (< x 1e+308))

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

  (- (cbrt (+ x 1.0)) (cbrt x)))