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