\sqrt[3]{x + 1} - \sqrt[3]{x}\begin{array}{l}
\mathbf{if}\;x \le -4.514659243240918023579410276165009573193 \cdot 10^{61}:\\
\;\;\;\;\left(0.3333333333333333148296162562473909929395 \cdot {\left(\frac{1}{{x}^{2}}\right)}^{\frac{1}{3}} + 0.06172839506172839163511412152729462832212 \cdot {\left(\frac{1}{{x}^{8}}\right)}^{\frac{1}{3}}\right) - 0.1111111111111111049432054187491303309798 \cdot {\left(\frac{1}{{x}^{5}}\right)}^{\frac{1}{3}}\\
\mathbf{elif}\;x \le 1.255581048238640526995287057963803650784 \cdot 10^{-10}:\\
\;\;\;\;\sqrt[3]{\sqrt[3]{x + 1} \cdot \sqrt[3]{x + 1}} \cdot \sqrt[3]{\sqrt[3]{x + 1}} - \left(\sqrt[3]{\sqrt[3]{x}} \cdot \sqrt[3]{\sqrt[3]{x}}\right) \cdot \sqrt[3]{\sqrt[3]{x}}\\
\mathbf{else}:\\
\;\;\;\;\frac{0 + 1}{\sqrt[3]{x + 1} \cdot \left(\sqrt[3]{x + 1} + \sqrt[3]{x}\right) + {x}^{\frac{2}{3}}}\\
\end{array}double f(double x) {
double r73821 = x;
double r73822 = 1.0;
double r73823 = r73821 + r73822;
double r73824 = cbrt(r73823);
double r73825 = cbrt(r73821);
double r73826 = r73824 - r73825;
return r73826;
}
double f(double x) {
double r73827 = x;
double r73828 = -4.514659243240918e+61;
bool r73829 = r73827 <= r73828;
double r73830 = 0.3333333333333333;
double r73831 = 1.0;
double r73832 = 2.0;
double r73833 = pow(r73827, r73832);
double r73834 = r73831 / r73833;
double r73835 = 0.3333333333333333;
double r73836 = pow(r73834, r73835);
double r73837 = r73830 * r73836;
double r73838 = 0.06172839506172839;
double r73839 = 8.0;
double r73840 = pow(r73827, r73839);
double r73841 = r73831 / r73840;
double r73842 = pow(r73841, r73835);
double r73843 = r73838 * r73842;
double r73844 = r73837 + r73843;
double r73845 = 0.1111111111111111;
double r73846 = 5.0;
double r73847 = pow(r73827, r73846);
double r73848 = r73831 / r73847;
double r73849 = pow(r73848, r73835);
double r73850 = r73845 * r73849;
double r73851 = r73844 - r73850;
double r73852 = 1.2555810482386405e-10;
bool r73853 = r73827 <= r73852;
double r73854 = 1.0;
double r73855 = r73827 + r73854;
double r73856 = cbrt(r73855);
double r73857 = r73856 * r73856;
double r73858 = cbrt(r73857);
double r73859 = cbrt(r73856);
double r73860 = r73858 * r73859;
double r73861 = cbrt(r73827);
double r73862 = cbrt(r73861);
double r73863 = r73862 * r73862;
double r73864 = r73863 * r73862;
double r73865 = r73860 - r73864;
double r73866 = 0.0;
double r73867 = r73866 + r73854;
double r73868 = r73856 + r73861;
double r73869 = r73856 * r73868;
double r73870 = 0.6666666666666666;
double r73871 = pow(r73827, r73870);
double r73872 = r73869 + r73871;
double r73873 = r73867 / r73872;
double r73874 = r73853 ? r73865 : r73873;
double r73875 = r73829 ? r73851 : r73874;
return r73875;
}



Bits error versus x
Results
if x < -4.514659243240918e+61Initial program 61.2
Taylor expanded around inf 41.7
if -4.514659243240918e+61 < x < 1.2555810482386405e-10Initial program 5.0
rmApplied add-cube-cbrt5.0
Applied cbrt-prod5.0
rmApplied add-cube-cbrt4.9
if 1.2555810482386405e-10 < x Initial program 57.6
rmApplied flip3--57.6
Simplified1.0
Simplified4.4
Final simplification11.9
herbie shell --seed 2019346
(FPCore (x)
:name "2cbrt (problem 3.3.4)"
:precision binary64
(- (cbrt (+ x 1)) (cbrt x)))