Re: DSolve test
- To: mathgroup at smc.vnet.net
- Subject: [mg132726] Re: DSolve test
- From: carlos.felippa%colorado.edu at gtempaccount.com
- Date: Mon, 12 May 2014 22:26:54 -0400 (EDT)
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On Sunday, May 11, 2014 10:46:04 PM UTC-6, Sasa B wrote:
> First, all the best to one of the most influential mechanics teacher of our
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> time, I'm glad to give this minor help :)
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> Bug doesn't seem fixed
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> sol = DSolve[{u'[t] == 2*Sqrt[u[t]], u[0] == 0}, u[t], t]; Print[sol];
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> returns
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> {{u[t]->t^2}}
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> (Mathematica 9, Intel 4570)
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> Aleksandar Borkovic
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> On Fri, May 9, 2014 at 8:07 AM, <
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> carlos.felippa%colorado.edu at gtempaccount.com> wrote:
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> > Hi, could somebody try this in Mathematica 9 to see if the bug is fixed?
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> > sol = DSolve[{u'[t] == 2*Sqrt[u[t]], u[0] == 0}, u[t], t]; Print[sol];
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> > Thanks.
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Thanks to all who replied. The bug is still there :-(
u=t=0 is a fixed branch point. Two solutions: u=0 and u=t^2.
DSolve only returns the latter.
I can give other examples if interested.
- References:
- DSolve test
- From: carlos.felippa%colorado.edu@gtempaccount.com
- DSolve test