2 \cdot \tan^{-1} \left(\sqrt{\frac{1 - x}{1 + x}}\right)\tan^{-1} \left(\sqrt{\frac{\sqrt[3]{1 - x} \cdot \sqrt[3]{1 - x}}{\frac{1 + x}{\sqrt[3]{\sqrt[3]{1 - x} \cdot \sqrt[3]{1 - x}} \cdot \sqrt[3]{\sqrt[3]{1 - x}}}}}\right) \cdot 2double f(double x) {
double r943737 = 2.0;
double r943738 = 1.0;
double r943739 = x;
double r943740 = r943738 - r943739;
double r943741 = r943738 + r943739;
double r943742 = r943740 / r943741;
double r943743 = sqrt(r943742);
double r943744 = atan(r943743);
double r943745 = r943737 * r943744;
return r943745;
}
double f(double x) {
double r943746 = 1.0;
double r943747 = x;
double r943748 = r943746 - r943747;
double r943749 = cbrt(r943748);
double r943750 = r943749 * r943749;
double r943751 = r943746 + r943747;
double r943752 = cbrt(r943750);
double r943753 = cbrt(r943749);
double r943754 = r943752 * r943753;
double r943755 = r943751 / r943754;
double r943756 = r943750 / r943755;
double r943757 = sqrt(r943756);
double r943758 = atan(r943757);
double r943759 = 2.0;
double r943760 = r943758 * r943759;
return r943760;
}



Bits error versus x
Results
Initial program 0.0
rmApplied add-cube-cbrt0.0
Applied associate-/l*0.0
rmApplied add-cube-cbrt0.0
Applied cbrt-prod0.0
Final simplification0.0
herbie shell --seed 2019174
(FPCore (x)
:name "arccos"
(* 2.0 (atan (sqrt (/ (- 1.0 x) (+ 1.0 x))))))