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Re: DSolve test

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  • Subject: [mg132710] Re: DSolve test
  • From: Bob Hanlon <hanlonr357 at gmail.com>
  • Date: Mon, 12 May 2014 00:41:43 -0400 (EDT)
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You did not say what bug or with which version. Version 9 gives a correct
solution for t >= 0



$Version


"9.0 for Mac OS X x86 (64-bit) (January 24, 2013)"



sol = DSolve[
   {u'[t] == 2*Sqrt[u[t]], u[0] == 0},
   u[t], t][[1, 1]]


u[t] -> t^2



u'[t] == 2*Sqrt[u[t]] /.
  NestList[D[#, t] &, sol, 1] //
 Simplify[#, t >= 0] &


True



u[0] == 0 /. (sol /. t -> 0)


True



Bob Hanlon




On Fri, May 9, 2014 at 2:07 AM, <
carlos.felippa%colorado.edu at gtempaccount.com> wrote:

> Hi, could somebody try this in Mathematica 9 to see if the bug is fixed?
>
> sol = DSolve[{u'[t] == 2*Sqrt[u[t]], u[0] == 0}, u[t], t]; Print[sol];
>
> Thanks.
>
>




  • References:
    • DSolve test
      • From: carlos.felippa%colorado.edu@gtempaccount.com
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