Trigonometria Dinâmica: unidade de aprendiza-gem online para estudo de Trigonometria

Digital technologies offer important opportunities for learning mathematics, using simulations, visualizations, modeling, experimentation, and other actions. With this in mind, the online learning unit "Dynamic Trigonometry" was developed for the study of Trigonometry in Secon- dary School. This unit has been fully developed by mathematics teachers and contains, among other features, 19 applets and a pack of investigative activities related to the applets. The unit was submitted to a validation process consisting of two parts: a preliminary validation was carried out by undergraduates and teachers in Mathematics, and a validation carried out by students of Secondary School. This article describes the validation process and analyzes the results, based on the socio-historical theory. From the analysis of the preliminary validation it was possible to improve the learning unit proposal. It stands out, moreover, that the partici- pants of this validation showed great interest in the potential of the applets, in view of the peda- gogical use of the same for the study of topics of Trigonometry. High school students, partici- pants of the validation, were attentive and motivated, trying to explore, as much as possible, the resources of the applets and thus understand the concepts discussed. The applets enabled views and simulations that supported the construction of knowledge.