.\" Copyright (c) 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)cos.3	5.1 (Berkeley) 05/02/91
.\"
.Dd 
.Dt COS 3
.Os
.Sh NAME
.Nm cos
.Nd cosine function
.Sh SYNOPSIS
.Fd #include <math.h>
.Ft double
.Fn cos "double x"
.Sh DESCRIPTION
The
.Fn cos
function computes the cosine of
.Fa 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
.Xr math 3 .
.Sh RETURN VALUES
The
.Fn cos
function returns the cosine value.
.Sh SEE ALSO
.Xr sin 3 ,
.Xr tan 3 ,
.Xr asin 3 ,
.Xr acos 3 ,
.Xr atan 3 ,
.Xr atan2 3 ,
.Xr sinh 3 ,
.Xr cosh 3 ,
.Xr tanh 3 ,
.Xr math 3 ,
.Sh STANDARDS
The
.Fn acos
function conforms to
.St -ansiC .