SQRT

NAME

sqrt, sqrtf, sqrtl - square root function

#include <math.h>

double sqrt(double x);

float sqrtf(float x);

long double sqrtl(long double x);

The sqrt() function returns the non-negative square root of x. It fails and sets errno to EDOM, if x is negative.

SVID 3, POSIX, BSD 4.3, ISO 9899. The float and the long double variants are C99 requirements.