Working with Balls and Intervals: An Introductory Approach to Topology
Topology, metric spaces, balls, intervals.
Topology is a branch of mathematics that studies the characteristics and properties of objects and shapes that, even when deformed, keep these properties. Developed from needs that were not only answered with knowledge of Geometry and improved over time with the discoveries of several illustrious mathematicians, this branch is commonly seen in higher education, however the following work was developed in order to present, in an introductory way, topics of Mathematical Topology that can be treated in high school considering the limitations of knowledge applied to the level of education - as the idea of intervals - and the knowledge already learned during the students’ journey. To this end, ways will be presented to introduce Topology ideas, like the concept of balls and spheres, through concepts already seen by students, allying also with concrete examples which can be found in their daily lives. We understand that the mastery of certain knowledge of the Topology of Metric Spaces brings greater comfort in dealing with the minutiae of mathematical models that involve the line and the plane. Here, the notion of metric is approached in a very intuitive way, since students are already used to the notion of distance between two points, either on the straight or on the plane.