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.\"     from: @(#)tanh.3	5.1 (Berkeley) 5/2/91
.\"
.Dd $Mdocdate: May 31 2007 $
.Dt TANH 3
.Os
.Sh NAME
.Nm tanh ,
.Nm tanhf
.Nd hyperbolic tangent functions
.Sh SYNOPSIS
.Fd #include <math.h>
.Ft double
.Fn tanh "double x"
.Ft float
.Fn tanhf "float x"
.Sh DESCRIPTION
The
.Fn tanh
function computes the hyperbolic tangent of
.Fa x .
The
.Fn tanhf
function is a single precision version of
.Fn tanh .
For a discussion of error due to roundoff, see
.Xr math 3 .
.Sh RETURN VALUES
The
.Fn tanh
and
.Fn tanhf
functions return the hyperbolic 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 tan 3
.Sh STANDARDS
The
.Fn tanh
function conforms to
.St -ansiC .