\frac{r \cdot \sin b}{\cos \left(a + b\right)}\frac{r}{\frac{\cos a \cdot \cos b - \sin a \cdot \sin b}{\sin b}}double f(double r, double a, double b) {
double r18833 = r;
double r18834 = b;
double r18835 = sin(r18834);
double r18836 = r18833 * r18835;
double r18837 = a;
double r18838 = r18837 + r18834;
double r18839 = cos(r18838);
double r18840 = r18836 / r18839;
return r18840;
}
double f(double r, double a, double b) {
double r18841 = r;
double r18842 = a;
double r18843 = cos(r18842);
double r18844 = b;
double r18845 = cos(r18844);
double r18846 = r18843 * r18845;
double r18847 = sin(r18842);
double r18848 = sin(r18844);
double r18849 = r18847 * r18848;
double r18850 = r18846 - r18849;
double r18851 = r18850 / r18848;
double r18852 = r18841 / r18851;
return r18852;
}



Bits error versus r



Bits error versus a



Bits error versus b
Results
Initial program 15.0
rmApplied cos-sum0.3
rmApplied associate-/l*0.4
Final simplification0.4
herbie shell --seed 2020089 +o rules:numerics
(FPCore (r a b)
:name "r*sin(b)/cos(a+b), A"
:precision binary64
(/ (* r (sin b)) (cos (+ a b))))