I am trying to learn how to solve a bunch of digital signal problems and I have trouble understanding the solutions provided by this book I'm using. Basically, this problem asks me to determine spectrum amplitudes for half-wave rectified sine, as the title mentions. The signal looks like this:
The development in complex (exponential) Fourier series will be given by:
What properties are used to get to this answer? I don't get from where did the came from.
I was missing the red n. From that and using