.\" Copyright (c) 1991 The Regents of the University of California.
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.\"     from: @(#)tan.3	5.1 (Berkeley) 5/2/91
.\" $FreeBSD: src/lib/msun/man/tan.3,v 1.9 2001/10/13 12:23:23 bde Exp $
.\"
.Dd May 2, 1991
.Dt TAN 3
.Os
.Sh NAME
.Nm tan ,
.Nm tanf
.Nd tangent functions
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn tan "double x"
.Ft float
.Fn tanf "float x"
.Sh DESCRIPTION
The
.Fn tan
and the
.Fn tanf
functions compute the tangent 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 tan
function returns the tangent value.
.Sh SEE ALSO
.Xr acos 3 ,
.Xr asin 3 ,
.Xr atan 3 ,
.Xr atan2 3 ,
.Xr cos 3 ,
.Xr cosh 3 ,
.Xr math 3 ,
.Xr sin 3 ,
.Xr sinh 3 ,
.Xr tanh 3
.Sh STANDARDS
The
.Fn tan
function conforms to
.St -isoC .