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Undetermined coefficients

  1. Nov 3, 2014 #1
    Hi there, I know that when I am to guess a solution to to a polynomial for g(t) that I guess Ax^n + Bx^n-1... when the highest power of the polynomial is n but what is my guess supposed to be if the power of n is negative?

    y'' + 4y' + 4y = t^-2*e^(-2t)

    so far my guess is,

  2. jcsd
  3. Nov 3, 2014 #2


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  4. Nov 3, 2014 #3


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    To add to SteamKing's link, you don't even try undetermined coefficients if n is negative, because it won't work.
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