Re: Problem with DSolve
- To: mathgroup at smc.vnet.net
- Subject: [mg96495] Re: Problem with DSolve
- From: dh <dh at metrohm.com>
- Date: Sat, 14 Feb 2009 03:14:24 -0500 (EST)
- References: <gn3bnf$pt9$1@smc.vnet.net>
Hi Tony,
solve first the general problem:
sol = y[x] /. DSolve[{y'[x] == .02*y[x] - y[x]^2}, y[x], x][[1]]
then determine the constant C[1]:
Solve[(sol /. x -> 0) == a, C[1]]
hope this helps, Daniel
Tony wrote:
> can anyone help what is wrong?
> On version 7 I enter
>
> DSolve[{y'[x]==.02*y[x]-y[x]^2,y[0]==a},y[x],x]
>
> and get
>
> During evaluation of In[58]:= Solve::ifun: Inverse functions are being used by Solve, so some solutions may not be found; use Reduce for complete solution information. >>
> During evaluation of In[58]:= Solve::ifun: Inverse functions are being used by Solve, so some solutions may not be found; use Reduce for complete solution information. >>
> During evaluation of In[58]:= DSolve::bvnul: For some branches of the general solution, the given boundary conditions lead to an empty solution. >>
>