Re: Square root of a square
- To: mathgroup at smc.vnet.net
- Subject: [mg107841] Re: Square root of a square
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Sun, 28 Feb 2010 04:53:44 -0500 (EST)
- Reply-to: hanlonr at cox.net
FullSimplify[Sqrt[x^2] == x] True This is wrong since for real x, Sqrt is always non-negative and x could be = negative. x = -3; Sqrt[x^2] == x False Bob Hanlon ---- "Mariano Su=C3=A1rez-Alvarez" <mariano.suarezalvarez at gmail.com> wrote:= ============= Hi all, Mathematica evaluates FullSimplify[Sqrt[x^2]] to Sqrt[x^2], while it tells me that FullSimplify[Sqrt[x^2] == x] is True. Are these the expected answers? -- m