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Re: Solving Third Order differential equation using Mathematica.

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  • Subject: [mg127389] Re: Solving Third Order differential equation using Mathematica.
  • From: Murray Eisenberg <murray at math.umass.edu>
  • Date: Fri, 20 Jul 2012 23:42:40 -0400 (EDT)
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  • Reply-to: murray at math.umass.edu

I cannot answer your question now, but I did notice two things about 
your differential equation:

  (1) You have an expression (1 - ax)^7.  Should "ax" actually be "a x" 
(i.e., a product of a and x, rather than a new constant "ax")?

   (2) You also have an expression (1 - y). By any chance should that be 
(1 - x)?


On 7/20/12 3:51 AM, amitesh wrote:
> Hi,
>
> I am trying to solve a third order differential eqn in mathematica.
> DSolve[{1/30 f'''[x] - f[x] (2 a^3/(1 - x a)^3 + 1/(1 - x)^3) - 24 a/
> (1 - y) (1/(1 - x)^7 - a^5/(1 - ax)^7) == 0, f[0] == 0,
>     f''[0] == 0}, f[x], x]
>   I am running this eqn for last 1 hour :/ why does Mathematica take so
> much time?
>
> Will Mathematica able to solve this eqn?
>
>
> Thanks
> Amitesh
>

-- 
Murray Eisenberg                     murray at math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower      phone 413 549-1020 (H)
University of Massachusetts                413 545-2859 (W)
710 North Pleasant Street            fax   413 545-1801
Amherst, MA 01003-9305



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