Description:The core of this book, is a large number of problems and their solutions that have been obtained simultaneously with the help of Maple and Mathematica. The structure of the book consists of the two parts.In Part I, the foundations of the computer algebra systems Maple and Mathematica are discussed, starting from the introduction, basic concepts, elements of language (Chapters 1 and 2).In Part II, the solutions of mathematical problems are described with the aid of the two computer algebra systems Maple and Mathematica and are presented in parallel, as in a dictionary. We consider a variety areas of mathematics that appeal to students such as algebra, geometry, calculus, complex functions, special functions, integral transforms, and mathematical equations (Chapters 3–10).