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Binomial Theorem

How do I put a quadratic like (1-x+x^2)^-1 in a form where I can use binomial theorem? I've tried completing the square but you end up with a quartic in the expansion.


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(1-(x-x^2))^-1

You should know the expansion of (1-y)^-1. So just replace the y's with (x-x^2).

Hint: (1-y)^-1 = 1+y+y^2+y^3+...
(edited 7 years ago)

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