Re: Sqrt[R^2]
- To: mathgroup at smc.vnet.net
- Subject: [mg42758] Re: Sqrt[R^2]
- From: "Dana DeLouis" <delouis at bellsouth.net>
- Date: Fri, 25 Jul 2003 05:08:03 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Just something slightly different. In Mathematica 5, one can use "$Assumptions". Here, all single small letters are assumed to be >=0. $Assumptions = (Symbol[#1] >= 0 & ) /@ CharacterRange["a", "z"]; Simplify[Sqrt[b^2]] b Simplify[Sqrt[s^2]] s Simplify[Sqrt[z^2]] z I am not sure, but from help menu on "Assumptions" ..."Variables in an inequality are implicitly assumed to be real." Therefore, I don't believe you need to use ? \[Element] Reals. (but I may be wrong) -- Dana DeLouis Windows XP Mathematica 5.0 for Microsoft Windows delouis at bellsouth.net = = = = = = = = = = = = = = = = = "Prechtl Josef" <e9426270 at stud4.tuwien.ac.at> wrote in message news:bfl2q4$shh$1 at smc.vnet.net... > How can I instruct Mathematica when simplifying expressions to convert > expressions e.g. Sqrt[R^2] into R? i.e. only to restrict to the case > that the variable R is a positive real? > > thank you in advance for any help! >