26 Numerics library [numerics]

26.8 Mathematical functions for floating-point types [c.math]

double       beta(double x, double y);
float        betaf(float x, float y);
long double  betal(long double x, long double y);

Effects: These functions compute the beta function of their respective arguments x and y.

Returns:

B (x, y) = \frac{Γ (x) Γ (y)}{Γ (x + y)}, for x > 0, y > 0,

where x is x and y is y.