Re: Problems with simplify and Sqrt[a^2]
- To: mathgroup at smc.vnet.net
- Subject: [mg73896] Re: [mg73845] Problems with simplify and Sqrt[a^2]
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Sat, 3 Mar 2007 00:48:59 -0500 (EST)
- Reply-to: hanlonr at cox.net
Sqrt[(-3)^2]
3
expr=v3/Sqrt[v1^2]/Sqrt[v2^2]-v3/v1/v2;
Simplify[expr,{v1>0,v2>0}]
0
Bob Hanlon
---- dshortho <david.shorthouse at credit-suisse.com> wrote:
> any help on this one:
>
> if you type in:
> v3/Sqrt[v1^2]/Sqrt[v2^2] - v3/v1/v2
>
> you get the same expression
>
> Even if you then type
> Simplify[%]
>
> you still get the same expression
>
> I would have thought Mathematica would have resolved Sqrt[v1^2] to v1 (!?)
>
> Does anyone out there know why it does not do this, as it is causing some problems with some proofs I am doing ?
>