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%colora...@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.
>
>