.\" Copyright (c) 1985, 1991 Regents of the University of California.
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.\"     from: @(#)asinh.3	6.4 (Berkeley) 5/6/91
.\" $FreeBSD: src/lib/msun/man/asinh.3,v 1.10 2001/10/13 12:23:22 bde Exp $
.\"
.Dd May 6, 1991
.Dt ASINH 3
.Os
.Sh NAME
.Nm asinh ,
.Nm asinhf
.Nd inverse hyperbolic sine functions
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn asinh "double x"
.Ft float
.Fn asinhf "float x"
.Sh DESCRIPTION
The
.Fn asinh
and the
.Fn asinhf
functions compute the inverse hyperbolic sine
of the real
argument
.Ar x .
For a discussion of error due to roundoff, see
.Xr math 3 .
.Sh RETURN VALUES
The
.Fn asinh
and the
.Fn asinhf
functions
return the inverse hyperbolic sine of
.Ar x .
.Sh SEE ALSO
.Xr acosh 3 ,
.Xr atanh 3 ,
.Xr exp 3 ,
.Xr math 3
.Sh HISTORY
The
.Fn asinh
function appeared in
.Bx 4.3 .