Re: Rearrange equation

*To*: mathgroup at smc.vnet.net*Subject*: [mg111586] Re: Rearrange equation*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Fri, 6 Aug 2010 06:57:50 -0400 (EDT)

I believe that you will have to use numeric techniques Manipulate[ FindRoot[ G == (Erfc[x]*(\[Mu] - Log[x]))/(2*Sqrt[2]*\[Sigma]), {x, 1}] // Chop, {{\[Mu], 0}, 0, 2.25, Appearance -> "Labeled"}, {{\[Sigma], 1}, .1, 5, Appearance -> "Labeled"}, {{G, 0}, 0, 4, Appearance -> "Labeled"}] Bob Hanlon ---- Tonja Krueger <tonja.krueger at web.de> wrote: ============= I want to rearrange the equation below so that it would look like: x-> .... I tried: Solve[G==-(Sqrt[\[Pi]/2]*Erfc[x]*(-\[Mu]+Log[x]))/(2*Sqrt[\[Pi]]*\[Sigma]),x] But then I got the error message: Solve::tdep: The equations appear to involve the variables to be solved for in an essentially non-algebraic way. Is there a way to solve the equation? Thanks Tonja