Hi, I'm taking a Chemistry NMR & MRI class and were going over the part where the time domain graph is converted to the frequency domain graph by way of the Fourier Transform. I took Applied Mathematics last semester and we spent a week on the Fourier Transform but no time on the Fourier sine or cosine transform.

From what I can tell, all periodic functions can be described as a sum of sine and cosine functions. The Fourier Transform of this can be divided into a real and imaginary part.

Does anyone have an example or two of say an expression before and after? And if possible a graph before and after? Like which part is the real and which the imaginary? If I'm wrong somewhere here I apologize and let me know please.

Thanks for any input!