xref: /freebsd/lib/msun/man/tanh.3 (revision dc36d6f9bb1753f3808552f3afd30eda9a7b206a)

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.Dd April 3, 2022
.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 .
.Sh HISTORY
The
.Fn tanh
function first appeared in
.At v7 .