sqrt Computes the square root of a number. Syntax #include <math.h> double sqrt (double x); Parameters x A real number. Return Values n The square root of the real number. 0 The x parameter is negative; errno is set to EDOM. Description Error handling can be changed by a user-written matherr function. See Also pow(), matherr(), ANSI C 4.5.5.2, POSIX.1 8.1