
Differential Equations Ordinary and Partial Differential Equations Math Forum 
 LinkBack  Thread Tools  Display Modes 
November 20th, 2007, 04:35 AM  #1 
Newbie Joined: Nov 2007 From: Sweden Posts: 1 Thanks: 0  differential equation problem
Hi, I am trying to solve the following differential equation: df(t)/dt = A*g(t)  D*f(t) where 'A' is a (positive) constant and D = B*g(t>infinity)/f(t>infinity) + C where 'B' and 'C' are constants (positive). The initial condition is f(0) = 0. The obvious problem is that the constant(?) 'D' is dependent on f, so in order to solve the equation 'D' must be known, but that requires in turn that f(t>infinity) is known. g(t) is continous (but its derivative may not be continous everywhere) and g(t)>0 when t>infinity (so f(t)>0 when t>infinity, but the limit g(t)/f(t) exists when t>infinity). I suppose that this problem has to be solved with numerical methods (iteration), but there is perhaps also an analytical solution to this problem. Maybe there is some standard method for this kind of problem? I would be grateful for any advice on how to solve this, analytically or numerically. Best regard, Mattias 

Tags 
differential, equation, problem 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Differential Equation Problem  stealth4933  Differential Equations  3  February 13th, 2014 07:01 AM 
Differential equation problem  rob747uk  Differential Equations  2  March 26th, 2012 09:55 AM 
Help with differential equation problem  sivela  Differential Equations  1  January 21st, 2011 06:53 PM 
differential equation problem  noul  Differential Equations  4  December 19th, 2010 05:34 AM 
Differential equation problem!  David McLaurin  Differential Equations  3  July 8th, 2009 08:50 AM 