Re: Convincing Mathematica that Sqrt[a+b]Sqrt[a-b]==Sqrt[a^2+b^2]
- To: mathgroup at smc.vnet.net
- Subject: [mg63286] Re: Convincing Mathematica that Sqrt[a+b]Sqrt[a-b]==Sqrt[a^2+b^2]
- From: "Jean.Pellegri" <Jean.Pellegri at wanadoo.fr>
- Date: Fri, 23 Dec 2005 05:08:14 -0500 (EST)
- References: <dod6vb$4fi$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Bonjour You can define a rule : In[1 := rule=Sqrt[a_- b_]Sqrt[a_+ b_]->Sqrt[a^2 - b^2] In[2] := Sqrt[a-b]Sqrt[a+b] /. rule Out[2] := Sqrt[a^2-b^2] Jean "Steven T. Hatton" <hattons at globalsymmetry.com> a écrit dans le message de news: dod6vb$4fi$1 at smc.vnet.net... > Is there a way to convince Mathematica to multiply Sqrt[a+b]Sqrt[a-b] to > produce Sqrt[a^2+b^2]? > -- > The Mathematica Wiki: http://www.mathematica-users.org/ > Math for Comp Sci http://www.ifi.unizh.ch/math/bmwcs/master.html > Math for the WWW: http://www.w3.org/Math/ >