Re: Are some equations unsolvable?
- To: mathgroup at smc.vnet.net
- Subject: [mg128068] Re: Are some equations unsolvable?
- From: "Kevin J. McCann" <kjm at KevinMcCann.com>
- Date: Thu, 13 Sep 2012 03:38:44 -0400 (EDT)
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A quick look at your function indicates that you have Sqrt[Pi/(-1/(2 sigma^2)))], which will give you an complex number for real sigma. Kevin On 9/12/2012 3:04 AM, Sergio Sergio wrote: > Hi, > This is what I have: > > f = (1/(sigma*Sqrt[2 Pi]))*Sqrt[(Pi/(-1/(2*sigma^2)))]* > Exp[((m/sigma^2)^2)/4*(-1/2*sigma^2) + (m^2/(2*sigma^2))] > > Solve[f == 216, sigma] > > And I get this message: "This system cannot be solved with the methods available to Solve" > > Is it because there is no way to isolate sigma? Or am I doing something wrong? > > Thanks >