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Second order equation

  1. Jan 29, 2007 #1
    d2y/dx2+k*dy/dx = du/dx+u

    anyone got a hint how to use ODE to sovle this inhomogenous equation?

    Thanks a lot
  2. jcsd
  3. Jan 29, 2007 #2


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    You can't solve a single differential equation for two different functions any more than you can solve a single algebraic equation for two different numbers.
  4. Jan 31, 2007 #3
    I would say that you may be able to solve this using the method of Frobenius, which ultimately means that you break it down into a root series problem. Although, I believe the person above me was correct in saying that you cannot solve this using traditional methods since you have three different variables.
  5. Jan 31, 2007 #4
    hmm I wonder if its possibly to rework this into a partial differential equation for x that is a function of u and y, while not giving you a nice litle functionfor u and y it will give you a general idea of the solution.
  6. Feb 1, 2007 #5


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    This equation seems to represent a dynamic system, where u is the input and y the output.
    You can use Laplace transforms to get a transfer function from u to y.
    To solve for y you must know the function u(x) and the initial conditions y(0) and y'(0).
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