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Student Support Forum: 'Num. Solution ordinary diff. equation??' topicStudent Support Forum > General > "Num. Solution ordinary diff. equation??"

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Ralf Becker
11/06/00 7:29pm


Hi -

I try to solve the following ODE:

NDSolve[ {4y''[x] + 2 y[x] y'[x] + 4 == 0, y[0] == 0, y'[1] == 0}, y, {x, 0, 1}]

and receive as a reply:

NDSolve::''pcnan'': ''Coefficients of the differential equation are not numbers \ or only one linear nth order ordinary differential equation can be solved.''

On the other hand, when I give as a second initial condition y'[0]=1 (or something like that) instead of a condition at the right boundary as in y'[1]==0, things work fine. Now, based on the Mathematica book what I did should work fine - plus, the error report doesn't seem to make sense given that IF there's a problem, it must be in the communication of boundary values. What's wrong?

Thanks heaps for any help!!!

Ralf

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Num. Solution ordinary diff. equation?? Ralf Becker 11/06/00 7:29pm
Re: Num. Solution ordinary diff. equation?? Forum Modera... 11/18/00 07:53am
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