xref: /freebsd/lib/msun/man/tanh.3 (revision fbbd9655e5107c68e4e0146ff22b73d7350475bc)

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.\"     from: @(#)tanh.3	5.1 (Berkeley) 5/2/91
.\" $FreeBSD$
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.Dd August 17, 2013
.Dt TANH 3
.Os
.Sh NAME
.Nm tanh ,
.Nm tanhf ,
.Nm tanhl
.Nd hyperbolic tangent functions
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn tanh "double x"
.Ft float
.Fn tanhf "float x"
.Ft long double
.Fn tanhl "long double x"
.Sh DESCRIPTION
The
.Fn tanh ,
.Fn tanhf ,
and
.Fn tanhl
functions compute the hyperbolic tangent of
.Fa x .
For a discussion of error due to roundoff, see
.Xr math 3 .
.Sh RETURN VALUES
The
.Fn tanh ,
.Fn tanhf ,
and the
.Fn tanhl
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 ctanh 3 ,
.Xr math 3 ,
.Xr sin 3 ,
.Xr sinh 3 ,
.Xr tan 3
.Sh STANDARDS
The
.Fn tanh
function conforms to
.St -isoC .