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Jigoro
03/21/13 03:11am

Dear Community members,

It is known that the solution to the problem

z''(t)-z'(t)-2*z(t) = 0, where z(0)=3, z'(0)=0 is given by

z(t) = Exp[2*t]+2*Exp[-t].

Yet, the commands

s = NDSolve[{z''[t] - z'[t] - 2*z[t] == 0, z[0] == 3, z'[0] == 0},
z, {t, -100, 100}]

Plot[Evaluate[z[t] /. s], {t, -100, 100}, PlotRange -> All]

reveal a wrong solution (namely, the function z spikes up at a different value of t than it should be).

Can you please help to find out the remedy to this issue?

Best regards,

Jigoro.



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Subject (listing for 'Strange NdSolve solution')
Author Date Posted
Strange NdSolve solution Jigoro 03/21/13 03:11am
Re: Strange NdSolve solution Bill Simpson 03/22/13 00:52am
Re: Re: Strange NdSolve solution Jigoro 03/23/13 05:29am
Re: Re: Strange NdSolve solution Jigoro 03/25/13 09:03am
Re: Re: Re: Strange NdSolve solution Bill Simpson 03/25/13 11:54am
Re: Re: Re: Re: Strange NdSolve solution Jigoro 03/26/13 05:21am
Re: Re: Re: Re: Re: Strange NdSolve solution Bill Simpson 03/26/13 1:16pm
Re: Re: Re: Re: Re: Re: Strange NdSolve solution jigoro 03/27/13 7:20pm
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