Volume 2 offers a straightforward approach to understanding the theory of several engineering tools used to compute, evaluate, and analyse practical problems. It is a mathematic textbook that can be used by students, instructors, and technical carriers; partially, the book also covers signal processing in the related course syllabus. Throughout the four chapters of the book, besides the pure mathematical examples, several practical issues from different fields are modelled and solved to illustrate the relation between the theory and its applications. The book elucidates the subjects in a self-contained style. The reader can select what he wants to read without following a particular sequence of reading. Volume 2 contains four chapters that consist of two units. The first two chapters deal with the continuous and discrete function (signal) analysis that is based on Fourier's series and transforms, and on the z-transform for the discrete functions. The considered functions are periodic as well as aperiodic. The second unit consists of special multivariable functions, specifically, the space vector and the complex functions. Each chapter is ended with exercises that are arranged according to the chapter sections. The readers will find the answers at the end of the book.