Principles of Mathematics for Economics and Business is a textbook born from the authors' desire to improve students' relationship with mathematics and to stimulate their curiosity about the potential of mathematics in economic and business studies. It is characterized by a presentation of topics that combines mathematical formalism with a simple approach, enriched by examples and economic applications. The book is aimed at students in undergraduate programs in economics and business, as well as anyone interested in studying the following topics: Functions of one variable, Linear algebra, Functions of two variables, Integrals and series, and First-order differential and difference equations.