S=sum of (-1)^n/n from 1 to infty

For why I named the post as so, here’s why

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Hint

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The solution I have in mind is related to the Taylor series


Hint 2

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It converges to -ln(2), but why


Solution:

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https://gmtex.siri.sh/fs/1/School/Extra/Maths/Qotd solutions/2024-06-02-alternating_harmonic.html

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There closest I was able to do on the fly was to show that the ::: pairwise sum has an integral of -ln(2)/2 ::: but that was pretty hand wavy. I’ll have to check how it’s actually done.

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2 points
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ln(2) because the Taylor series for ln(1+x) evaluated at x=1 is exactly this series.

Good one. Thanks for posting!

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yup thats the intended solution, im not really familiar with taylor series yet, but maybe for a person who knows taylor series would be able to see it right away

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