1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)cos.3 8.1 (Berkeley) 06/04/93 7.\" 8.Dd 9.Dt COS 3 10.Os 11.Sh NAME 12.Nm cos 13.Nd cosine function 14.Sh SYNOPSIS 15.Fd #include <math.h> 16.Ft double 17.Fn cos "double x" 18.Sh DESCRIPTION 19The 20.Fn cos 21function computes the cosine of 22.Fa x 23(measured in radians). 24A large magnitude argument may yield a result with little or no 25significance. 26For a discussion of error due to roundoff, see 27.Xr math 3 . 28.Sh RETURN VALUES 29The 30.Fn cos 31function returns the cosine value. 32.Sh SEE ALSO 33.Xr sin 3 , 34.Xr tan 3 , 35.Xr asin 3 , 36.Xr acos 3 , 37.Xr atan 3 , 38.Xr atan2 3 , 39.Xr sinh 3 , 40.Xr cosh 3 , 41.Xr tanh 3 , 42.Xr math 3 , 43.Sh STANDARDS 44The 45.Fn acos 46function conforms to 47.St -ansiC . 48