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Help undetermined coefficients

  1. Jul 11, 2009 #1
    i solved homogenous but
    y"+y'+4y = 2sinh(T)
    is giving me trouble
    also have a hint
    sinh t = (e^t - e^-t)/2

    also my "guess" was
    aE^t +Be^-t=Y
    maybe my guess was wrong?
  2. jcsd
  3. Jul 12, 2009 #2
    That should be fine.
  4. Jul 12, 2009 #3


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    Science Advisor

    Why are you asking? Have you tried putting that into the equation? If you are used to working with hyperbolic functions directly, you can also use y= C cosh(t)+ D sinh(t).
  5. Jul 12, 2009 #4
    tried this guess but yield wrong answer guess ill do a few more times thanks all
  6. Jul 12, 2009 #5
    In the "Homework" forum, you can put in your work with wrong answer, and ask where you went wrong.
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