TAN(3) | Library Functions Manual | TAN(3)

# NAME

`tan`, `tanf`, `tanl` — tangent functions

# SYNOPSIS

Math Library (libm, -lm)
`#include <math.h>`

double
`tan`(double x);

float
`tanf`(float x);

long double
`tanl`(long double x);

# DESCRIPTION

The `tan`() function computes the tangent of x (measured in radians). The `tanf`() function is a single precision version of `tan`(). The `tanl`() function is an extended precision version of `tan`(). A large magnitude argument may yield a result with little or no significance.

# RETURN VALUES

The `tan`(), `tanf`() and `tanl`() functions return the tangent value.

# SEE ALSO

acos(3), asin(3), atan(3), atan2(3), cos(3), cosh(3), sin(3), sinh(3), tanh(3)

# STANDARDS

The `tan`() function conforms to ANSI X3.159-1989 (“ANSI C89”).

June 7, 2025 | Debian