Integral x/(1-x) via power series?

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fahraynk
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So, ∫x/(1-x)... can I solve this as a power series

∫(x*Σ x^n) = ∫(Σ x^(n+1))= (1/(n+2)*Σ x^(n+2))?

Is this correct? I know there is other ways to do it... But should this be correct on a test? This solution is more fun..
 
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fahraynk said:
So, ∫x/(1-x)... can I solve this as a power series

∫(x*Σ x^n) = ∫(Σ x^(n+1))= (1/(n+2)*Σ x^(n+2))?

Is this correct? I know there is other ways to do it... But should this be correct on a test? This solution is more fun..

More fun than what? More fun than the exact expression? Is a solution of limited applicability (i.e., is correct only for limited values of x) preferable to one that applies to all x ≠ 1?
 
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Ray Vickson said:
More fun than what? More fun than the exact expression? Is a solution of limited applicability (i.e., is correct only for limited values of x) preferable to one that applies to all x ≠ 1?
Ha. Good point.