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Homework Help: Trouble evaluating the integral for a rational function

  1. Jan 15, 2009 #1
    1. The problem statement, all variables and given/known data
    i've tried many partial fraction methods but none of y answers are correct in the end, please help me evaluate the integral for f(x)= (10x+2)/(x-5)(x^2 + 1)

    2. Relevant equations

    there are no relevant equations given

    3. The attempt at a solution

    A/x-5 + Bx+C/x^2 +1
  2. jcsd
  3. Jan 15, 2009 #2


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    Homework Helper

    So now you have

    [tex]\frac{A(x^2+1)+(Bx+C)(x-5)}{(x-5)(x^2+1)}= \frac{10x+2}{(x-5)(x^2+1)}[/tex]

    So equating the numerators

    A(x^2+1)+(Bx+C)(x-5)= 10x+2 for all values of x.

    Try putting suitable values of x which will eliminate most of the constants. For example, x=5 will help you get A.
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