Article View: sci.math.symbolic
Article #1029Re: unexpected result
From: Arthur Rubin
Date: Wed, 27 Jan 1993 23:04
Date: Wed, 27 Jan 1993 23:04
27 lines
1381 bytes
1381 bytes
In <rvk.728154627@wink> rvk@blink.att.com (Bob Kline) writes:
> Running mma 2.1 on a Sparc-2, I input the following:
> Solve[{Sqrt[x]+y==11,x+Sqrt[y]==7},{x,y}].
> this results in four roots. substituting the result in
> Sqrt[x]+y (or Sqrt[y]+x), only two of the roots are
> correct. the other two are numbers like 14.nnn and 17.nnn.
Try setting the option VerifySolutions-> True.
By default, mma solves the equations:
{u^2 ==x,u+y==11,v^2==y,x+v==7}
and eliminates u and v. For the remaining solutions, u and/or v is
negative.
--
Arthur L. Rubin: a_rubin@dsg4.dse.beckman.com (work) Beckman Instruments/Brea
216-5888@mcimail.com 70707.453@compuserve.com arthur@pnet01.cts.com (personal)
My opinions are my own, and do not represent those of my employer.
My interaction with our news system is unstable; please mail anything important.
Technical Details
Message-ID:
<a_rubin.728175862@dn66>Path:
arc1-ca.pugleaf.net!sparky!uunet!math.fu-berlin.de!ira.uka.de!scsing.switch.ch!univ-lyon1.fr!ghost.dsi.unimi.it!rpi!usc!news.service.uci.edu!beckman.com!dn66!a_rubinReferences:
<rvk.728154627@wink>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!sparky!uunet!math.fu-berlin.de!ira.uka.de!scsing.switch.ch!univ-lyon1.fr!ghost.dsi.unimi.it!rpi!usc!news.service.uci.edu!beckman.com!dn66!a_rubin Newsgroups: sci.math.symbolic Subject: Re: unexpected result Message-ID: <a_rubin.728175862@dn66> From: a_rubin@dsg4.dse.beckman.com (Arthur Rubin) Date: 27 Jan 93 23:04:22 GMT References: <rvk.728154627@wink> Distribution: usa Organization: Beckman Instruments, Inc. Keywords: roots mma Nntp-Posting-Host: dn66.dse.beckman.com Lines: 27