Partial Fraction Integration - Set up problems?

demersal
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Homework Statement


\int\frac{2x^{2}}{(x^{2}-1)} dx


Homework Equations


Partial Fractions


The Attempt at a Solution


2\int\frac{x^{2}}{(x^{2}-1)} dx

2\int\frac{x^{2}}{(x-1)(x+1)} dx

\frac{A}{x-1} + \frac{B}{x+1} = \frac{x^{2}}{(x+1)(x-1)}

A(x+1) + B(x-1) = x^{2}

Solving for coefficients does not work because there is no x^{2} term of A or B and also when solving for the x and the constant contradictory answers occur. Did I set this up wrong??
 
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Perhaps try polynomial long divison first
 
I can't believe I didn't see that; thank you!
 
No problem :smile:
 
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