# FFT first frequency

I have some problems understanding FFT. If I know Fourier analysis frame (1024 samples) and sample rate (48 000 Hz), how can I find the first frequency of harmonic sines and cosines?

• Maybe this helps: the FFT is just a fast way to calculate the DFT. (read the DFT wikipedia article!) The DFT is a sum, and when you look at the $e^{j\ldots}$ functions, you'll see the frequencies jump right at you :) – Marcus Müller Nov 8 at 19:04