newbie: diff equation

*To*: mathgroup at smc.vnet.net*Subject*: [mg96886] newbie: diff equation*From*: Mike <atkins1976 at yahoo.com>*Date*: Thu, 26 Feb 2009 08:01:18 -0500 (EST)

My problem is very simple, I'm sure someone can help me out quickly. I am trying to solve some systems of differential equations a bit like a particle in a box (QM) so I started with this basic problem which I know how to solve just to make sure I am entering everything ok, but I can't even get it to work. I want to solve f''[x]= - m^2 f[x] with f[0] = 0 and f[Pi] = 0 this is obviously only solvable with the condition on m being integer but if I do DSolve on the above with the boundary conditions I just get f=0. How can I get mathematica to solve this and give me the conditions on m? I need to solve much more general problems of this type. I hope someone can help. Many thanks

**Follow-Ups**:**Re: newbie: diff equation***From:*DrMajorBob <btreat1@austin.rr.com>

**Re: newbie: diff equation***From:*"Ned Lieb" <okty.gy.ned@gmail.com>