Re: Integrate Problem
- To: mathgroup at smc.vnet.net
- Subject: [mg40506] Re: Integrate Problem
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Wed, 9 Apr 2003 01:29:16 -0400 (EDT)
- Organization: Universitaet Leipzig
- References: <b6tsvb$n20$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
Integrate[1/Pi^2 1/(1 + x^2 + y^2 + z^2)^2, {z, -Infinity, Infinity},
Assumptions -> {Im[x] == 0, Im[y] == 0, Im[z] == 0}] //
FullSimplify[#, Im[x] == 0 && Im[y] == 0 && Im[z] == 0] &
Regards
Jens
Stewart Mandell wrote:
>
> When I run
>
> Integrate[1/Pi^2 1/(1 + x^2 + y^2 + z^2)^2, {z, -Infinity, Infinity},
> Assumptions -> {Im[x] == 0, Im[y] == 0, Im[z] == 0}]
>
> I get
> (I*(Log[-(I/Sqrt[1 + x^2 + y^2])] -
> Log[I/Sqrt[1 + x^2 + y^2]]))/
> (2*Pi^2*(1 + x^2 + y^2)^(3/2))
>
> I would like
>
> 1/(2*Pi ) 1/(1 + x^2 + y^2)^3/2
>
> for an answer. How do I get Mathematica to forego the complex
> answer?
>
> thanks, Stewart