Fourier Series coefficients, orthogonal?

[Dollydaggerxo]

Homework Statement

Hello. I need help with orthogonality of the Fourier series coefficients. I know you can use the dirac delta function, (or the kronecker function) in the orthogonality relationship. I want to try and see the derivation using complex form rather than sines and cosines.

Homework Equations

proof of
\frac{1}{T}\int^T_0 e^{inw_0t}e^{-imw_0t} dt = \delta_{m}{n}

The Attempt at a Solution

Basically I haven't got very far, do not know where to start in this proof. any help would be appreciated?

thanks

 

[susskind_leon]

Obviously, m and n must be integers, which makes things really easy. Just assume m=n, do the integration and write down what you get. Then assume m \neq n, do the integration and write down what you get.

 

[Dollydaggerxo]

Okay I have got it. Thanks!