Simplify: Which Sign
- To: mathgroup at smc.vnet.net
- Subject: [mg16831] Simplify: Which Sign
- From: Remi Ricard <ricard at gmc.ulaval.ca>
- Date: Tue, 30 Mar 1999 02:35:27 -0500
- Sender: owner-wri-mathgroup at wolfram.com
I, How can you know which sign the Fonction Simplify will give you My equation is eq1 = 4 C1^4 - 8 C1^2 lm1^2 + 4 lm1^4; Using eq1 = Simplify[eq1]; I get eq1 = 4 (-C1^2 + lm1^2)^2; which could have been eq1 = 4 (C1^2 - lm1^2)^2; Since eq1 will be the input of a square root, I want to be able to decide which of the + or - solution I will use. C1 = lm1 Cos[theta_1]; lm1 > 0; +------------------------------------------------------------+ + Remi Ricard | Lab. : (418) 656-2131 #6302 + + Departement Genie Mecanique | Fax. : (418) 656-7415 + + Universite Laval | + + Quebec, Qc | + + G1K 7P4 | Email : ricard at gmc.ulaval.ca + + Canada | + +------------------------------------------------------------+ + Page Web : http://wwwrobot.gmc.ulaval.ca/~ricard + +------------------------------------------------------------+