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# The sum or a series Watch

1. I have a series that I think might be a Maclaurin one, but I'm not sure:

1/4 - 1/(2(4^2)) + 1/(3(4^3)) - ..... + ( (-1)^(k+1) )/(k(4^k))

And I have to find it's sum. Does anyone know where to start? I'm not even sure how to get the general term of the sequence.

Please help!

Thanks in advance
2. You've already been given the general term of the sequence.. it's ( (-1)^(k+1) )/(k(4^k))

And you're right, it is a maclaurin one, so why not compare it to some series for some common functions, and see if you can spot which it might be related to
3. You've already written the form of the general term?

All I can suggest for this is look at the list of Maclaurin series on this page: http://en.wikipedia.org/wiki/Taylor_series and try to spot which one to use.

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Updated: November 29, 2010
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