Re: Rearrangement of expression
- To: mathgroup at smc.vnet.net
- Subject: [mg91748] Re: Rearrangement of expression
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Sun, 7 Sep 2008 05:35:19 -0400 (EDT)
- References: <g9t6np$j9n$1@smc.vnet.net>
Hi,
expr = a/Sqrt[a^2 + b^2];
expr //. { (a^2 + q_)^(Rational[n_, 2]) :>
Abs[a]^n*(1 + q/a^2)^(Rational[n, 2]), a_/Abs[a_] :> Sign[a]}
Regards
Jens
Gehricht at googlemail.com wrote:
> Hi!
>
> Suppose I have the fraction a/Sqrt[a^2+b^2]. How can I rearrange it to
> 1/Sqrt[1+(b/a)^2]?
> With thanks
> Yours Wolfgang
>