""BASIC MATH. An Introduction to Calculus" is an easy way to learn to learn mathematics with four main chapters; the first is based on set theory, the numerical system and the real straight with the Cartesian system from the plane and space. The second chapter shows applications of the theory of sets, permutations, combinations, relations and functions. The third chapter illustrates translations and functional models with the types of functions: real, polynomial, constant, linear, quadratic, exponential, logarithmic, trigonometric and inverse function. The fourth chapter develops equations and inequalities, along with linear or nonlinear systems of equations and inequalities. The fifth chapter concludes with solved recapitulation exercises. This work is aimed at university students in traditional academic programs or distance education in economic, administrative, social and humanistic sciences.