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Homework Help: Difference equation

  1. Feb 11, 2009 #1
    1. The problem statement, all variables and given/known data
    Given difference equation
    T(a+2)-7T(a+1) +6T(a)= 6f
    Find the general solution of this equation

    2. Relevant equations
    I have found the auxiliary equation be
    A(1)^n+B(6)^n
    But seems can't find the particular solution of that question.
    Is it impossible to do this question?


    3. The attempt at a solution
     
  2. jcsd
  3. Feb 12, 2009 #2

    tiny-tim

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    Hi haoku! :smile:
    What's f? :confused:
     
  4. Feb 12, 2009 #3

    HallsofIvy

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    f is a constant? Then "trying" a constant as solution won't work because a constant already satisfies the homogeneous equation (n0= 1). Try T(n)= Cn as a solution and determine C.
     
  5. Feb 14, 2009 #4
    Sorry this is 6a
     
  6. Feb 14, 2009 #5

    tiny-tim

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    ah! :biggrin:

    in that case, try a polynomial in a. :smile:
     
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