This book is written at a pretty low level, so I wonder about the lack of worked examples and motivation. The classical diagram for aliasing of a time-domain sine function is shown, but the frequency domain is not. I don’t think we see a spectra plotted until the chapter on digital signals at the end.<p>Are there a lot of people out there who know what integrals are and are comfortable reading them, but need a refresher on complex number arithmetic?