Tangent

[Classification]

Mathematical library

[Syntax]

#include <math.h>

double tan(double x);

[Return value]

Returns the tangent of x.

If inputting +, tan returns a Not a Nuber(NaN) and sets macro EDOM to global variable errno.

If the solution is a denormal number, tan sets macro ERANGE to global variable errno.

[Description]

This function calculates the cosine of x. Specify the angle in radian.