Re: Dsolve ODE
- To: mathgroup at smc.vnet.net
- Subject: [mg89137] Re: Dsolve ODE
- From: dh <dh at metrohm.ch>
- Date: Mon, 26 May 2008 06:25:07 -0400 (EDT)
- References: <g18hoc$kft$1@smc.vnet.net> <g1avme$fbo$1@smc.vnet.net>
Hi,
the initial conditions can not be the reason for failure as the
following example shows:
DSolve[{y''[x]+4y[x]==0,y[0]==1,y[Pi/4]==4},y,x]Daniel
Steven Siew wrote:
> On May 24, 5:57 pm, sokol <mirek.h... at gmail.com> wrote:
>> Hello, I've tried to solve 2nd order ODE with Dsolve but failed.
>>
>> In[1]:
>> DSolve[{y''[x] + Cot[x]*y'[x] + Sin[x]*y[x] == 0,
>> y[\[Pi]/2] == \[Alpha], y[(7*\[Pi])/8] == \[Beta]}, y[x], x]
>>
>> out[1]:
>> DSolve[{y''[x] + Cot[x]*y'[x] + Sin[x]*y[x] == 0,
>> y[\[Pi]/2] == \[Alpha], y[(7*\[Pi])/8] == \[Beta]}, y[x], x]
>>
>> Any hint? Thanks.
>
> I believe that your initial conditions are insufficient.
>
> I think you need
>
> y'[x1]==something
> y[x2]==something else
>
> for your initial conditions
>
--
Daniel Huber
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