If you're coming from a synthesis background, you're probably well familiar with a sine wave, it is the fundamental building block of sound, after all. But if you think back to high school, you might remember using sine and cosine to figure out angles on a triangle. How do those two things relate?
While this is a math-related video, you're not going to have to do any of it -- this is just about understanding how things relate to one another.
This is sorta-kinda video 4.5 in my series on FM synthesis. If you'd like to follow along with it, here's a link to the playlist: ruclips.net/p/PLUKhEHilRBxQydqw_kiAdAhegPZMgjVCX