Lei da reciprocidade quadrática e problemas olímpicos

Abstract

In this dissertation we will know techniques that will allow us to tell if the congruence x 2 = a (mod m) admits or not solution, this is equivalent to saying whether or not a is a quadratic residue module m, where a, m e Z and (a, m) = 1. We will see important tools such as Legendre symbol and Lemma of Gauss. Hence, we will demonstrate the Law of Quadratic Reciprocity, the theorem that calls this work. In addition, we will present some applications of this theorem, highlighting the problems of international mathematics olympiads.