Re: Checking the sign of a Mathematical expression

*To*: mathgroup at smc.vnet.net*Subject*: [mg66426] Re: Checking the sign of a Mathematical expression*From*: "Steve Luttrell" <steve_usenet at _removemefirst_luttrell.org.uk>*Date*: Fri, 12 May 2006 02:03:02 -0400 (EDT)*References*: <e3uodm$i9u$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Here are two examples of what you want: Simplify[Sign[x^2],x>0] 1 Simplify[Sign[Sin[x]^2],0<x<Pi] 1 Steve Luttrell West Malvern, UK "Bharat Bhole" <bbhole at gmail.com> wrote in message news:e3uodm$i9u$1 at smc.vnet.net... > > Hello: > > Is there a way in Mathematica to check whether an algebraic expression is > positive or negative, and a way to specify conditions on the variables in > the expression? For example, is there a way to check whether x^2 is > positive > for any real x? I want to check this for a complicated > expression...basically the sign of the second derivative of a function. > > Thank you very much for your help. > > I am sorry for posting this message again. I had not used the appropriate > subject line and thought I should change it. > >