2 \cdot \tan^{-1} \left(\sqrt{\frac{1 - x}{1 + x}}\right)2 \cdot \tan^{-1} \left(\sqrt{\frac{1 - x}{1 + x}}\right)double f(double x) {
double r11094 = 2.0;
double r11095 = 1.0;
double r11096 = x;
double r11097 = r11095 - r11096;
double r11098 = r11095 + r11096;
double r11099 = r11097 / r11098;
double r11100 = sqrt(r11099);
double r11101 = atan(r11100);
double r11102 = r11094 * r11101;
return r11102;
}
double f(double x) {
double r11103 = 2.0;
double r11104 = 1.0;
double r11105 = x;
double r11106 = r11104 - r11105;
double r11107 = r11104 + r11105;
double r11108 = r11106 / r11107;
double r11109 = sqrt(r11108);
double r11110 = atan(r11109);
double r11111 = r11103 * r11110;
return r11111;
}



Bits error versus x
Results
Initial program 0.0
Final simplification0.0
herbie shell --seed 2020024 +o rules:numerics
(FPCore (x)
:name "arccos"
:precision binary64
(* 2 (atan (sqrt (/ (- 1 x) (+ 1 x))))))