perplexus.info :: Just Math : Great Divide

Great Divide (Posted on 2020-06-15)

Let
P1=a+a²+a³... +a¹⁰⁰
and
P2=a^-1+a^-2+a^-3... +a^-100

Evaluate P1/P2.

No Solution Yet Submitted by Ady TZIDON

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One way to see the solution

| Comment 1 of 3

If you multiply P2 by a^101 it will perfectly match P1. So the ratio simplifies to a^101.

(It took me a while to see this so I agree with the difficulty rating.)

Posted by Jer on 2020-06-15 12:13:17

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