The main thopic of this final thesis is Basic functions in economy. Functions are basic part of mathematics, so the thesis defines concept of a function and the terms that are crutial for its definition. Subsequently, the basic mathematical properties of elementary functions are defined and the types of functions with graphical and algebraic representations are enumerated and explained. The main part of the paper defines the economic terms in which the properties of these functions are used. The supply, the demand functions and the state of the market equilibrium are explained. The application of elementary functions in economics and their interpretation are presented in solving the problems of supply and demand. Then, the application of elementary functions to the examples of cost, income, and profit is presented. An interest rate account with exponential function applications is further explained. The purpose of the paper was to point out the importance of functions in mathematics and their application in economics.