Why does ∑(-1)^n/(n+1) at x=1 equal log(2)?

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DottZakapa
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Homework Statement
##\sum_{n=0}^\infty (-1)^n \frac {x^\left(n+1\right)}{n+1}## for x=1
Relevant Equations
power series
##\sum_{n=0}^\infty (-1)^n \frac {x^\left(n+1\right)}{n+1}## for x=1

##\sum_{n=0}^\infty (-1)^n \frac {1^\left(n+1\right)}{n+1}##

i've tried leibniz test but i can only find that it converges

why is this power equal to ##log(2)##?

i've also tried with ##\sum_{n=0}^\infty\log \left (1+\frac 1 {n+1}\right)##

but does not lead to that result

what am i missing ?
 
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Hint: Try integrating the series for ##\frac{1}{1+x}##.
 
vela said:
Hint: Try integrating the series for ##\frac{1}{1+x}##.

which is log(1+x)
:doh:
ok, didn't understood that if it converges i could plug there the value of x to see at which value converges. Thank you. :smile: