Re: PowerExpand, Apart, Simplify
- To: mathgroup at smc.vnet.net
- Subject: [mg5670] Re: [mg5654] PowerExpand, Apart, Simplify
- From: rhall2 at umbc.edu (hall robert)
- Date: Tue, 7 Jan 1997 11:22:46 -0500
- Organization: University of Maryland, Baltimore County
- Sender: owner-wri-mathgroup at wolfram.com
In article <5ap4kr$kv2 at dragonfly.wolfram.com>, Allan Hayes <hay at haystack.demon.co.uk> wrote: >"Lidar (Hamburger) dani" <dani at fh.huji.ac.il> > [mg5654] PowerExpand, Apart, Simplify > writes > >> ...I have not been able to find any way to make Mathematica >>tell me that the following expression equals 1 (using the built-in >>functions,that is): >> >>Sqrt[3 x^(4j)+x^(12j)]/(x^(2j)Sqrt[3 + x^(8j)]) >>(x,j real and positive) > > >Dani: > >Factor//@Sqrt[3 x^(4j)+x^(12j)]/(x^(2j)Sqrt[3 + x^(8j)]) > 4 j 8 j > Sqrt[x (3 + x )] > --------------------- > 2 j 8 j > x Sqrt[3 + x ] > >PowerExpand[%] > 1 > >?//@ > MapAll[f, expr] or f //@ expr applies f to every > subexpression in expr. Using 2.2.2, MapAll isn't necessary. In[6]:= Sqrt[3 x^(4j)+x^(12j)]/(x^(2j)Sqrt[3 + x^(8j)]) Out[6]= 4 j 12 j Sqrt[3 x + x ] -------------------- 2 j 8 j x Sqrt[3 + x ] And PowerExpand[] doesn't work. In[7]:= PowerExpand[%] Out[7]= 4 j 12 j Sqrt[3 x + x ] -------------------- 2 j 8 j x Sqrt[3 + x ] -- Bob Hall | "Know thyself? Absurd direction! rhall2 at gl.umbc.edu | Bubbles bear no introspection." -Khushhal Khan Khatak