Tuesday, 10 October 2017

Sum of alternating harmonic series

Edit: As @FamousBlueRaincoat pointed out below, this question was based on an error in a wikipedia article.



The Wikipedia article on the harmonic series gives the following "proof without words" that the alternating harmonic series $1-1/2 +1/3 -1/4 + \cdots $ converges to $\log (2) $:

\begin{equation}
(1/1)(1/1 - 1/2) + (1/2)(2/3 -2/4) + (1/4)(4/5 - 4/6 + 4/7 - 4/8) + \cdots
= \log (2).
\end{equation}



Can anyone explain why the sum on the left is $\log (2) $? I don't see it right now.



Edit: my goal is specifically to understand this "proof without words" that the alternating harmonic series converges to $\log(2)$.

No comments:

Post a Comment

real analysis - How to find $lim_{hrightarrow 0}frac{sin(ha)}{h}$

How to find $\lim_{h\rightarrow 0}\frac{\sin(ha)}{h}$ without lhopital rule? I know when I use lhopital I easy get $$ \lim_{h\rightarrow 0}...