Here is a YouTube video about Eulers Identity and the Fourier Transform, and is part of a growing collection of videos I have found to be useful. The reason is how to relate Euler's identity to understanding the Fourier transform and understanding science related to software defined radio.
This tutorial, "Eulers Identity and the Fourier Transform" is free education you can watch, which will help you deepen your knowledge and be better prepared for licence exams, schoolwork, or operating radio equipment.