A introdução da definição de Função Afim no 9º ano do ensino fundamental

Abstract

This research aims to investigate the approach for the concept and the definition related to function in the 9th grade of elementary school. As teachers, we are interested in to help students in understanding the concept and definition of function. According to its objective, we conducted an exploratory study that included a case study with qualitative analysis of the data. Thus, we analyzed the didactic book adopted at the school and we elaborated a diagnosis with the students of the 9th grade of Elementary School of a State School of the municipality of Araçagi, Paraíba. The results of the analysis of these data allowed us to reach some conclusions: the students presented several answers when asked about what they mean by afine function, but without being able to present it coherently. They associate this concept with representations using first degree equation or the law of formation or even graphs in the cartesian plane, tables and sets. The use of a textbook is not enough to work with the concept of function before presenting its definition; there are some possibilities for the introduction of the concept of function as: natural language, writing systems (numerical, algebraic and symbolic), Cartesian graphics and geometric figures, which can be represented through five forms of representation; Verbal registration; Training Law; Tabulated data; Venn Diagram and Graphics. Finally, we affirm that the present study indicates possibilities to treat the introduction of the concept of function in Elementary School.