+.\" Copyright (c) 1985, 1991, 1993
+.\" The Regents of the University of California. All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\" notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\" notice, this list of conditions and the following disclaimer in the
+.\" documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\" must display the following acknowledgement:
+.\" This product includes software developed by the University of
+.\" California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\" may be used to endorse or promote products derived from this software
+.\" without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" @(#)sqrt.3 8.1 (Berkeley) 6/4/93
+.\"
+.Dd June 4, 1993
+.Dt SQRT 3
+.Os
+.Sh NAME
+.Nm cbrt ,
+.Nm sqrt
+.Nd cube root and square root functions
+.Sh SYNOPSIS
+.Fd #include <math.h>
+.Ft double
+.Fn cbrt "double x"
+.Ft double
+.Fn sqrt "double x"
+.Sh DESCRIPTION
+The
+.Fn cbrt
+function computes
+the cube root of
+.Ar x .
+.Pp
+The
+.Fn sqrt
+computes the
+non-negative square root of x.
+.Sh RETURN VALUES
+The
+.Fn cbrt
+function returns the requested cube root.
+The
+.Fn sqrt
+function returns the requested square root
+unless an error occurs.
+On the
+.Tn VAX
+or
+.Tn Tahoe
+processor an attempt to take the
+.Fn sqrt
+of negative
+.Fa x
+causes an error; in this event,
+the global variable
+.Va errno
+is set to
+.Dv EDOM
+and a reserved operand fault is generated.
+.Sh ERROR (due to Roundoff etc.)
+The
+.Fn cbrt
+function
+is accurate to within 0.7
+.Em ulps .
+.Pp
+The
+.Fn sqrt
+function on a
+.Tn VAX
+is accurate to within 0.501
+.Em ulps .
+Sqrt on a machine that conforms to
+.Tn IEEE
+754 is correctly rounded
+in accordance with the rounding mode in force; the error is less than
+half an
+.Em ulp
+in the default mode (round\-to\-nearest).
+An
+.Em ulp
+is one
+.Em U Ns nit
+in the
+.Em L Ns ast
+.Em P Ns lace
+carried.
+.Sh SEE ALSO
+.Xr math 3 ,
+.Xr infnan 3
+.Sh STANDARDS
+The
+.Nm sqrt
+function conforms to
+.St -ansiC .
+.Sh HISTORY
+The
+.Nm cbrt
+function appeared in
+.Bx 4.3 .
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