How do I pick out the expression under a radical?
- To: mathgroup at smc.vnet.net
- Subject: [mg36225] How do I pick out the expression under a radical?
- From: asb4 at psu.edu (Steve Beach)
- Date: Tue, 27 Aug 2002 02:07:36 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
I'm a poor physicist trying to figure out how to sort out the "physical" from the "non-physical" solutions to a problem. To do that, I need to be able to look at an expression and pick out a subexpression, the part under the radical. For example, say I've got the expression a b x^2 + 5 x^3 + 5 Sqrt[4 - x^2] I'd like to pick out "4 - x^2", which would then tell me that x is between +/- 2. I know there has got to be an easy way to do it, but I can't find it. Any help would be appreciated. Thanks, Steve Beach asb4 at psu.edu http://www.thebeachfamily.org