This article presents the results of a research carried out on the use of GeoGebra Mathematical Assistant in the teaching-learning process of differential calculus. This content deals with variation, movement, quantities that change and depend on other quantities, being considered by manypeopleasone of the great achievements of the human intellect. Differential calculus has a derivative concept considered fundamental for its study, as it is a linear operator, which forms a new function from the original, in which each point of the new function is the displacement of the original one. Its teaching has raised several difficulties for Secondary School students, such as: differential concept and derivative of a function at a point, geometric interpretation of derivative, rules of derivation and its applications in solving exercises and mathematical problems, lack of mathematical skills, determination of the growth and decrease intervals of a function, among others. These difficulties were identified through questionnairesand interviews carried out onteachers and 12th grade students, whose data were processed by the SPSS statistical software. The results showed that the visualization provided by GeoGebra in two-dimensional space proved to be an indispensable component in the construction of derivative concept. Based on these results, a didactic strategy was developed to favor the teaching-learning process of differential calculus using GeoGebra Mathematical Assistant in order to contribute to reducing these difficulties.
