I am working with problems which are taking a toll on me.(adsbygoogle = window.adsbygoogle || []).push({});

1st and 3rd partial sums of the sequence An=(-2)^n+5

----I don't even know what formula to use to start this problem

and sum of hte geometric series:

2/3 - 4/9 + 8/27 - ...

I think I use this formula for this one: S=A1/1-r

Please help

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# Series, Sequence and Probablility Question

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