Re: Simplifying Expressions containing SQRT

*To*: mathgroup at smc.vnet.net*Subject*: [mg3158] Re: Simplifying Expressions containing SQRT*From*: danl (Daniel Lichtblau)*Date*: Fri, 9 Feb 1996 03:01:35 -0500*Organization*: Wolfram Research, Inc.*Sender*: owner-wri-mathgroup at wolfram.com

In article <4f4hsq$cpu at dragonfly.wolfram.com> lieres at studm.hrz.uni-siegen.de (Eric von Lieres) writes: > Hi everybody! > > Strange things do happen! > > Mathematica4s ability to simplify equitations containing square roots > seems to be quite weak. Perhaps I just do not know enough about these > things, but I did read the manual. An example: > > Sqrt [ R ( R - x ) ] Sqrt [ ( R - x ) x ] / ( R x - R^2 ) > > > equals Sqrt[ R / x ], but I can4t get Mathematica figure that out. > > I tried PowerExpand, Factor, Collect, Simplify and almost everything > else in various orders. Nothing worked! What can I do? > > I do appreciate every helpful hint. Thank you very much. > > > Eric von Lieres lieres at studm.hrz.uni-siegen.de > > ------------------------------------------------------------ > Eric von Lieres lieres at studm.hrz.uni-siegen.de > They seem not to be equal. In[7]:= Sqrt [ R ( R - x ) ] Sqrt [ ( R - x ) x ] / ( R x - R^2 ) - Sqrt[ R / x ] /. {R->-1, x->1} Out[7]= -2 I Daniel Lichtblau Wolfram Research, Inc. danl at wolfram.com ==== [MESSAGE SEPARATOR] ====