Re: Strange empty set of solutions
- To: mathgroup at smc.vnet.net
- Subject: [mg71793] Re: Strange empty set of solutions
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Wed, 29 Nov 2006 02:56:35 -0500 (EST)
- Organization: Uni Leipzig
- References: <ekh7pg$sgs$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
Hi, and we can't read you mind and the memory of your computer so we must imagine a matrix M and write down Solve[{{{1, 2, 3}, {2, 4, 6}, {1, -10, 0}}.{a, b, c} == {0, 0, 0}, a^2 + b^2 + c^2 == 1}, {a, b, c}] and got two solutions ... Regards Jens José Carlos Santos wrote: > Hi all, > > I have a certain 3 x 3 numerical matrix M. If I type > > Solve[M.{a,b,c}=={0,0,0},{a,b,c}] > > I get > > {{a -> 0. + 0.0410026 c, b -> 0. + 1.35294 c}} > > However, if I type > > Solve[{M.{a,b,c}=={0,0,0},a^2+b^2+c^2==1},{a,b,c}] > > I get the empty set. Why is that? I should get two solutions! > > Best regards, > > Jose Carlos Santos >