Re: False result with Integrate ?
- To: mathgroup at smc.vnet.net
- Subject: [mg8729] Re: False result with Integrate ?
- From: "Stephen P Luttrell" <luttrell at signal.dra.hmg.gb>
- Date: Sat, 20 Sep 1997 22:27:58 -0400
- Organization: Defence Evaluation and Research Agency
- Sender: owner-wri-mathgroup at wolfram.com
Gilles BARBIER <Gilles.Barbier at der.edfgdf.fr> wrote in article
<5vt8tj$gjg at smc.vnet.net>...
> Why : Integrate[Integrate[ Sqrt[(x-y)^2],{x,0,1}],{y,0,1}]
> gives 0 with math2.2 or math3.0.
>
> The exact result is 1/3 !!
It seems that Mathematica is simplifying Sqrt[(x-y)^2] to x-y.
Try the following way of doing your integral:
2 Integrate[Integrate[ x-y,{x,y,1}],{y,0,1}]
--
Stephen P Luttrell
luttrell at signal.dra.hmg.gb
Adaptive Systems Theory 01684-894046 (phone)
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