(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the sum of the infinite series: 405-270+180-120+80....

2. Relevant equations

??

3. The attempt at a solution

I know there's a formula for this but I can't remember it. Could someone refresh my memory?

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# Homework Help: Infinite Series

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