Re: positive root only using Solve[]
- To: mathgroup at smc.vnet.net
- Subject: [mg41804] Re: positive root only using Solve[]
- From: bobhanlon at aol.com (Bob Hanlon)
- Date: Fri, 6 Jun 2003 09:50:35 -0400 (EDT)
- References: <bbnaqt$2e2$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Select[Solve[x^2 ==1, x], #[[1,2]]>0&] {{x -> 1}} Select[Solve[x^2 ==1, x], (x/.#)>0&] {{x -> 1}} Bob Hanlon In article <bbnaqt$2e2$1 at smc.vnet.net>, "seferiad" <seferiad at pacbell.net> wrote: << Subject: positive root only using Solve[] From: "seferiad" <seferiad at pacbell.net> To: mathgroup at smc.vnet.net Date: Thu, 5 Jun 2003 11:50:53 +0000 (UTC) Hello, Consider the following equation. Solve[x^2 ==1, x] Mathematica will output 1 and -1 for x. However, I only want Mathematica to output the positive solution (i.e., x -> 1), so I can use this conveniently in a subsequent equation. Is there a way to force the output to produce only the positive solution? Thanks, Jay >><BR><BR>