NAME
cos, cosf, cosl – cosine functions
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
cos(double x);
float
cosf(float x);
long double
cosl(long double x);
DESCRIPTION
The cos(), cosf(), and cosl() functions compute the cosine of x (measured in radians). A large magnitude argument may yield a result with little or no significance. For a discussion of error due to roundoff, see math(3).
RETURN VALUES
The cos(), cosf(), and cosl() functions return the cosine value.
SEE ALSO
acos(3), asin(3), atan(3), atan2(3), ccos(3), cosh(3), math(3), sin(3), sinh(3), tan(3), tanh(3)
STANDARDS
These functions conform to ISO/IEC 9899:1999 (“ISO C99”).
HISTORY
The cos() function first appeared in Version 1 AT&T UNIX.