\cos^{-1} \left(\frac{1 - 5 \cdot \left(v \cdot v\right)}{v \cdot v - 1}\right)\sqrt[3]{{\left({\left(\cos^{-1} \left(\frac{1 - 5 \cdot \left(v \cdot v\right)}{v \cdot v - 1}\right)\right)}^{\left(\sqrt{3}\right)}\right)}^{\left(\sqrt{3}\right)}}double code(double v) {
return ((double) acos((((double) (1.0 - ((double) (5.0 * ((double) (v * v)))))) / ((double) (((double) (v * v)) - 1.0)))));
}
double code(double v) {
return ((double) cbrt(((double) pow(((double) pow(((double) acos((((double) (1.0 - ((double) (5.0 * ((double) (v * v)))))) / ((double) (((double) (v * v)) - 1.0))))), ((double) sqrt(3.0)))), ((double) sqrt(3.0))))));
}



Bits error versus v
Results
Initial program 0.5
rmApplied add-cbrt-cube1.4
Simplified1.4
rmApplied add-sqr-sqrt0.5
Applied pow-unpow0.5
Final simplification0.5
herbie shell --seed 2020196
(FPCore (v)
:name "Falkner and Boettcher, Appendix B, 1"
:precision binary64
(acos (/ (- 1.0 (* 5.0 (* v v))) (- (* v v) 1.0))))