Re: mathematica gives strange result

*To*: mathgroup at smc.vnet.net*Subject*: [mg111279] Re: mathematica gives strange result*From*: "J. Batista" <jbatista800 at gmail.com>*Date*: Mon, 26 Jul 2010 06:36:53 -0400 (EDT)

I'm not sure what you are anticipating, but the result generated by Mathematica is correct based on the information you provided. The result is a complex mathematical expression that may look strange to you, but the y(x) found by Mathematica satisfies the original differential equation. Don't forget, your original differential equation hosts a transcendental function. When we deal with transcendental functions, there is the possibility that several solvers may end up with answers that appear to be different, but in fact are equivalent mathematical expressions. You didn't provide initial conditions, so I assumed a value for C[1] and C[2] (these are the two expected constants generated by Mathematica as part of the solution) and plotted y(x). Be careful, depending on the value of x, you may be dealing with complex numerical values. Regards, J. Batista On Sun, Jul 25, 2010 at 1:57 AM, SNC <snc at irc.pl> wrote: > Im trying to find a solution to equation DSolve[-y''[x] + > ((Csc[x])^2)*y[x] == y[x]/4, y[x], x] but mathematica gives me some > strange result with expresion (-1+cos^2(x))^(1/4) in it. Why is that > and how should i interpretate this? > >