To find the sum of a fourier series ?

1. Apr 20, 2007

cabellos

to find the sum of a fourier series....?

My problem is:

I must find the sum of ((-1)^(n+1))/2n-1 between infinity and n=1.

I have looked in all my available textbooks for a clear example but im still unsure as to how i should approach the problem?

Help with this would be much appreciated.

Thankyou.

2. Apr 20, 2007

Dick

Do you really have to sum it, or just show it converges? The former is easy. I'm not sure how to do the latter unless someone can think of a taylor series that resembles your series.

3. Apr 20, 2007

Dick

Try this. Take the series for log(1+x) and think about putting x=i.

4. Apr 20, 2007

HallsofIvy

Staff Emeritus
But that's not a "Fourier series", that's just a power series.