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Homework Help: Series Solutions!

  1. Oct 27, 2008 #1
    1. The problem statement, all variables and given/known data
    1. Using series solution to solve dy/dx - y(x) = x where y(0) = -1. [y(x) = Σ ak x^k from 0 to infinity.
    2 Find c0 and c1 in y(x) = c0 e^αx + c1 e^-αx so that y(x) = a0 cosh(αx) +(a1/α) sinh (αx)
    3. Find the 2 independent solutions of x d2y/dx2 + 2 dy/dx +xy = 0 using the frobenius solution with r = 0, -1

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Oct 27, 2008 #2


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    Science Advisor

    You seem to have left out "The attempt at a solution". Certainly no deep thinking is required. Find the first derivative of [itex]y= \sum_0^\infty a_k x^k[/itex] and put those two series into dy/dx- y= x.
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