Exception for Area of a triangle

\[0.0 \lt a \land 0.0 \lt b \land 0.0 \lt c\]

Math

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

C

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

Reproduce

herbie shell --seed 2020078 
(FPCore (a b c)
  :name "Area of a triangle"
  :precision binary64
  :pre (and (< 0.0 a) (< 0.0 b) (< 0.0 c))
  (sqrt (* (* (* (/ (+ (+ a b) c) 2) (- (/ (+ (+ a b) c) 2) a)) (- (/ (+ (+ a b) c) 2) b)) (- (/ (+ (+ a b) c) 2) c))))