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Undetermined coefficients

  1. Jan 22, 2009 #1


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    How do I go about solving a DE using the method of undetermined coeficients in a question like for example;


    I tried assuming the yp to be Ae^2x but when I plugged it into the DE I ended up with 0=2e^2x

  2. jcsd
  3. Jan 22, 2009 #2


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    Homework Helper

    Since '2' double root of your aux. eq'n.

    the yp should be Ax^2e^2x
  4. Jan 22, 2009 #3


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    Once you substitute back into the original DE
    Do you get:

    8Ax^2e^2x + 2Ae^2x = 2e^2x
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