Square wave exponential fourier series

[Funnynick]

This is A and B my friend is telling me that Co is actually 0 and I am getting 1/2 and i don't see exactly what I am doing wrong if i indeed am doing something wrong hopefully someone here can check this out and let me know exactly where i went wrong..
Thanks

 

[DrClaude]

You wrote yourself that $c_n = 0$ when $n$ is even.

 

[rude man]

I can't get the second image to open.

 

[Funnynick]

Thanks for the reply, i figured out my mistake and redid the problem completely and found the correct answer.

Thanks