Construções dos números reais voltadas para os professores da rede básica de ensino

Abstract

This work aims to show that the set of real numbers is a complete ordered field that, within an isomorphism, is unique. This work is aimed at all those who are interested in mathematics, especially for that high school math teacher who uses the real numbers of the set of properties without knowing the mathematical theory involved. Therefore, it is necessary to characterize the set of the real in order to prove their properties. Here, we use two buildings, namely: the real via Cauchy sequences due to Cantor and the real via Dedekind cuts. From these characterizations, we can build a field K equipped with the addition and multiplication operations which show that it meets the definition of field conditions. Set an order relation in K, we show that such a body is ordered and in addition, we show that every subset of K admits supreme, which means that such a field is complete. Finally, we show that any complete ordered field that can, perchance appear is a mere characterization of ℝ, which means that ℝ is unique, unless these possible other characterizations. This characterization will be called isomorphism which is a function bijetora of ℝ to K.