- #1
Heirot
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Homework Statement
Prove: [tex]\sum_{i=1}^{\infty}\sum_{j=1}^{i-1} \frac{(-1)^i}{i j}=\frac{1}{2}\ln^2 2[/tex]
Homework Equations
[tex]\ln 2 = \sum_{i=1}^{\infty} \frac{(-1)^{i+1}}{i}[/tex]
The Attempt at a Solution
I'm trying to manipulate the l.h.s. of the problem to transform it into [tex]\frac{1}{2}\sum_{i=1}^{\infty}\sum_{j=1}^{\infty} \frac{(-1)^{i+j}}{i j}[/tex] but I just can't seem to get it.
Any suggestions will be appreciated.