Hi I am dealing with problem that says f(t)=ƩFn.exp(inwt) . f(t)=f(t+T) show that if f(t)=f[t+T/2) then Fn is zero for odd n? Attempt: I wrote formula for Fn=1/T∫f(t).exp(-inwt) and then just replace f(t) by f(t+T). but I do not get anything, I do not know how I should approach this problem. Any help would be highly appreciated?