r \cdot \frac{\sin b}{\cos \left(a + b\right)}\frac{r}{\frac{\cos a \cdot \cos b}{\sin b} - \sin a}double code(double r, double a, double b) {
return ((double) (r * ((double) (((double) sin(b)) / ((double) cos(((double) (a + b))))))));
}
double code(double r, double a, double b) {
return ((double) (r / ((double) (((double) (((double) (((double) cos(a)) * ((double) cos(b)))) / ((double) sin(b)))) - ((double) sin(a))))));
}



Bits error versus r



Bits error versus a



Bits error versus b
Results
Initial program 14.8
rmApplied cos-sum0.3
Taylor expanded around inf 0.3
Simplified0.4
rmApplied associate-*r/0.4
Final simplification0.4
herbie shell --seed 2020184
(FPCore (r a b)
:name "rsin B"
:precision binary64
(* r (/ (sin b) (cos (+ a b)))))