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Homework Help: Question about differential equations(nonhomogenous)?

  1. Feb 28, 2009 #1
    For this nonhomogeneous differential equation:

    -2y''+y'+y=2t^2-2t-5e^(-2t)

    would the setup for the particular solution (yp) be;
    Ae^(-2t)+Bt^2+Ct+D?

    Thank You
     
  2. jcsd
  3. Feb 28, 2009 #2

    Mark44

    Staff: Mentor

    It depends on the solutions to the homogeneous problem.

    What are the solutions to -2y'' + y' +y = 0?

    Or, equivalently, 2y'' - y' - y = 0?

    If the roots of the characteristic equation for the homogeneous equation aren't r = 0 or r = -2, then, yes, that's what you want for your particular solution.
     
  4. Feb 28, 2009 #3
    the roots are -.5 and 1
     
  5. Feb 28, 2009 #4

    djeitnstine

    User Avatar
    Gold Member

    Edit, nevermind I think its fine
     
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