Re: Convincing Mathematica that Sqrt[a+b]Sqrt[a-b]==Sqrt[a^2+b^2]
- To: mathgroup at smc.vnet.net
- Subject: [mg63284] Re: Convincing Mathematica that Sqrt[a+b]Sqrt[a-b]==Sqrt[a^2+b^2]
- From: Bhuvanesh <lalu_bhatt at yahoo.com>
- Date: Thu, 22 Dec 2005 00:04:49 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
> Is there a way to convince Mathematica to multiply > Sqrt[a+b]Sqrt[a-b] to produce Sqrt[a^2+b^2]? Simplify with assumptions can do it: In[1]:= Simplify[Sqrt[a + b]*Sqrt[a - b], a >= b] //InputForm Out[1]//InputForm= Sqrt[a^2 - b^2] Of course, that equality isn't true in general. Bhuvanesh, Wolfram Research.