# Intro Physics Books on Phase and Amplitude of a sine wave

1. Jul 28, 2015

### CupOfAppleTea

Hi!
I am searching for litterature on the decomposition of a sine wave in its three parameters: phase, frequency and amplitude. I just need it to justify an analysis that I am doing this way and it appears to be hard to find such a book. I find many website but nothing I can cite seriously!
Thanks!

2. Jul 28, 2015

### Dr. Courtney

3. Jul 29, 2015

### vanhees71

This is not so difficult. Just try it yourself! The effort is worth more than reading a lot of books! You just need the theorems
$$\sin(\alpha+\beta)=\sin \alpha \cos \beta + \sin \beta \cos \alpha, \quad \cos(\alpha+\beta)=\cos \alpha \cos \beta-\sin \alpha \sin \beta.$$