Funções trigonométricas e aplicações: uma proposta didática para o ensino médio usando o geogebra

When we look to the results of the wide scale evaluations that exist in Brazil, such as, National High School Exam - ENEM and the Evaluation System of Basic Education - SAEB, it is visible that mathematical learning process is not happening as expected. This fact stimulates researches in mathematical education to look out for reasons and possible solutions to this matter. Brito and Morey (2004) and Feijó (2018) for example, tried to understand respectively the problems faced by students and teachers when studying trigonometry, concluding that there is a necessity in changing the applied methodology. In face of the above, came the concernment in organizing a material which could help math teachers when facing trigonometric function classes on high school, using resources beyond the book and the whiteboard, and standing on the three fundamental tendencies of mathematical teaching. Math history, technological resources and problem solving. Therefore, this work aimed to develop a resource which supply the known necessities. This material is divided in four classes and on each one we cover the required topics to the fourth class, in which we study trigonometrical functions. On these classes, we looked at the historical facts that contributed to the development of trigonometry along with the content presentation proposed by the GeoGebra software. At the end we explained some applications of trigonometrical functions on day-to-day life, also suggesting contextualized questions used on the latest editions of ENEM and some Sat's. We hope that this work may help in rescuing a satisfactory mathematical learning process