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Find Yp for an especial ODE

  1. May 5, 2007 #1
    Edit: SOLVED!
    **********************
    Please help me find Yparticular for this ODE:

    y''-3y'-10y=exp(x)
    ......
    m^2-3*m-10=0 -> Yh = c1*exp(-5x)+c2*exp(2x)
    Yp = ?

    Thank you!
     
    Last edited: May 6, 2007
  2. jcsd
  3. May 6, 2007 #2
    This was a question in my midterm exam which I coudn't figure out. My midterm is over now! I just want to find the answer :confused:
     
  4. May 6, 2007 #3

    cronxeh

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    Gold Member


    Aww you changed it to exp(x)
    :devil:
     
  5. May 6, 2007 #4
    sorry! I mistyped.. in case of exp(1), it was very easy! Yh=-exp(1)/10
    exp(x) makes it really hard for me! I can't use Guessing mehtod or even Wronskian!
     
  6. May 6, 2007 #5
    no!
    sqrt(3^2-4(-10))=sqrt(49)=7
     
  7. May 6, 2007 #6

    cronxeh

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    :eek:

    true true :biggrin:


    see what happens when you are a year out of college you forget basic stuff :frown:
     
  8. May 6, 2007 #7
    Oops!
    It was very easy! I got it.
    Guessing Method:
    Yp= k*exp(x) ---> Yp=-exp(x)/12
     
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