2026-10-222026-10-222025-09-24SILVA, Josué Augusto Gonçalves da, O ensino das funções seno e cosseno por atividades experimentais com o Geogebra Belém. Orientador: Pedro Franco de Sá. 2025. 274 f. Dissertação (Mestrado Profissional em Ensino de Matemática) - Centro de Ciências Sociais e Educação, Universidade do Estado do Pará, Belém, 2025.https://portaldaposgraduacao.uepa.br/handle/riuepa/381AbertoFunções seno e cossenoEducação matemáticaEngenharia didáticaAplicativo GeogebraSine and cosine functionMathematics educationDidactic engineeringGeoGebra applicationDissertaçãoCiências Exatas e da Terra::MatemáticaCiências Humanas::Educação::Ensino-AprendizagemCiências Humanas::Educação::Ensino-Aprendizagem::Tecnologia EducacionalThis work aims to present a study on the trigonometric functions sine and cosine through experimental activities supported by the GeoGebra application. The choice of the investigated topic—trigonometric functions—was made due to the fact that it is a subject most high school students, particularly those in the 2nd year, consider complex and excessively abstract. The guiding question of this research is: What are the contributions of implementing a didactic sequence, developed from the perspective of Experimental Activities, that could enhance the teaching and learning process of sine and cosine functions for 2nd-year high school students with the help of GeoGebra on smartphones? The general objective of this research is to investigate the contributions of a didactic sequence aimed at improving the teaching and learning of sine and cosine trigonometric functions among 2nd-year high school students using the GeoGebra application. The initial setting of this research was the public school EEEM Professora Antonia Rosa, located in the municipality of São João da Ponta, Pará, Brazil. The subjects were 2nd-year high school students. We adopted the Teaching of Mathematics through Experimental Activities based on Sá (2019) and Problem Solving, based on Polya (1995) and Sá (2019), as the teaching methodology. Our research methodology is based on the ideas and assumptions of Didactic Engineering, a methodological approach within Mathematical Didactics proposed by Artigue (1995), which comprises four stages. In the first stage, called preliminary analysis, we included bibliographic research such as dissertations, articles, theses, educational documents, and textbook analyses that address relevant aspects of the topic, along with interviews with mathematics teachers about the content. In the second stage, known as conception and a priori analysis, we present our didactic sequence, based on the experimental activities of Corrêa (2016), in which we developed GeoGebra applets to be used in nine activities on sine and cosine functions. In the third stage, we chose to use a questionnaire for the validation of our Didactic Sequence by mathematics teachers. In the analysis and discussion, the results showed that the Didactic Sequence has strong potential for teaching sine and cosine functions using GeoGebra, enriching classes with a technological approach that is rarely used and encouraging greater student participation throughout the activity. Based on this, we developed an educational product related to our didactic sequence and also an online book on the GeoGebra website, composed of multiple-choice questionsPPGEM - Metodologia para ensino de matemática no nível médio