Re: Incorrect integral in Mathematica

*To*: mathgroup at smc.vnet.net*Subject*: [mg91389] Re: Incorrect integral in Mathematica*From*: amzoti <amzoti at gmail.com>*Date*: Tue, 19 Aug 2008 07:16:41 -0400 (EDT)*References*: <g8b8t8$8pq$1@smc.vnet.net>

On Aug 18, 12:38 am, Eran Mukamel <emuka... at stanford.edu> wrote: > Hi All, > > I'm getting a nonsensical answer of 0 for the following integral in Mathe= matica 5.0 (Mac OSX): > > Integrate[Exp[-x^2/(2w^2)]Exp[-(y - y0)^2/(2z^2)], > {x, -Infinity, Infinity}, {y, -Infinity, Infinity}] > > The result should be (2 Pi w z). Any ideas why this fails? > > Thanks in advance, Eran I tried this integral in version 4 on a PC and got the correct answer (although in a slightly different form).: (2*Pi)/(Sqrt[1/w^2]*Sqrt[1/z^2])