Exception for (acos (/ (- (+ (* b b) (* c c)) (* a a)) (* (* 2 b) c)))

Math

\[\cos^{-1} \left(\frac{\left(b \cdot b + c \cdot c\right) - a \cdot a}{\left(2 \cdot b\right) \cdot c}\right)\]

C

double code(double b, double c, double a) {
	return ((double) acos(((double) (((double) (((double) (((double) (b * b)) + ((double) (c * c)))) - ((double) (a * a)))) / ((double) (((double) (2.0 * b)) * c))))));
}

Reproduce

herbie shell --seed 2020153 
(FPCore (b c a)
  :name "(acos (/ (- (+ (* b b) (* c c)) (* a a)) (* (* 2 b) c)))"
  :precision binary64
  (acos (/ (- (+ (* b b) (* c c)) (* a a)) (* (* 2.0 b) c))))