freebsd man page for cos

COS(3)							   BSD Library Functions Manual 						    COS(3)

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'').

BSD
								 January 24, 2008							       BSD