Re: Simplfying inside Sqrt

*To*: mathgroup at smc.vnet.net*Subject*: [mg55127] Re: [mg55106] Simplfying inside Sqrt*From*: "David Park" <djmp at earthlink.net>*Date*: Sun, 13 Mar 2005 04:57:46 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

Bill, How about... {Sqrt[x^2 + x^4], 1/Sqrt[x^2 + x^4]}; % /. Power[a_, q : (1/2) | (-1/2)] :> Power[Factor[a], q] Refine[%, x > 0] {Sqrt[x^2*(1 + x^2)], 1/Sqrt[x^2*(1 + x^2)]} {x*Sqrt[1 + x^2], 1/(x*Sqrt[1 + x^2])} David Park djmp at earthlink.net http://home.earthlink.net/~djmp/ From: billkavanagh at gmail.com [mailto:billkavanagh at gmail.com] To: mathgroup at smc.vnet.net Hi I'm wondering how to tell mathematica that I want terms like Sqrt[x^2+x^4] to be x*Sqrt[1+x^2]. I have an expression with a few terms like this in it so manually inserting a PowerExpand[Sqrt[Expand[x^2+x^4]] is no good to me. I've tried a general PowerExpand and Simplify with a Im[x]==0 around the whole expression but with no luck. Does anybody know how to do this? Thanks, Bill -- William R. Kavanagh http://www.physics.mun.ca/~wkavanag