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Re: Need Help: 1st order nonlinear differential equation

  • To: mathgroup at smc.vnet.net
  • Subject: [mg51251] Re: [mg51215] Need Help: 1st order nonlinear differential equation
  • From: Wolfgang Eggert <Wolfgang_Eggert at gmx.de>
  • Date: Sun, 10 Oct 2004 01:57:28 -0400 (EDT)
  • References: <200410080655.CAA25036@smc.vnet.net> <opsfkkolkviz9bcq@monster.cox-internet.com>
  • Sender: owner-wri-mathgroup at wolfram.com

Bob, thank you very much.

At 23:01 08.10.2004, you wrote:
>That's totally unreadable. I recommend Omega Consulting's "Copy as 
>InputForm" palette:
>
>http://eclecticdreams.net/DrBob/copy_as_inputform.htm
>
>Bobby

My problem is:

I need to solve the following 1st order nonlinear differential equation. I 
am really stuck. DSolve refuses to give an answer and I need the algebraic 
solution for a[Z].


Derivative[1][a][Z] == (a[Z]*((-1 + n)*r* (n - Z*(2*\[Delta] + \[Rho])) + 
n*(1 + r - n*r)*a[Z]))/ ((-1 + n)*(n*(-1 + r) - 2*r)*r*Z*(-n + Z*\[Delta] + 
n*a[Z]))

where


\!\(1 \[GreaterEqual] a \[GreaterEqual] 0, n > 2, Z > 0, 1 > \[Delta] > 0, 
1 > \[Rho] > 0, 1 > r > 0, 0 < r < n\/\(\(-2\) + n\); \)


Does anybody know how to solve this problem?

Has anybody tips how to impose domain restrictions while solving 
differential equations in
Mathematica (version 5.0.1.0.)?


Maybe I am thinking slow but I am really in trouble.


Any help is greatly appreciated. Thank you for your time.


Respectfully;
Wolfgang  


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