Fourier Cosine series of cos(x)

[sarahisme]

Hello peoples,

I think this is a trick question... well sort of :P



for part (a) i get that the cosine Fourier Series for f(x) = cos(x) to be:



i hope that is ok, but its part (b) that is troubling me...

is all that happens as is that the cosine Fourier series of cos(x) goes to 0?

i am guessing i am missing some trick to this question?

Cheers!

Sarah

[sarahisme]

its cool, don't worry i got it!