Didactic use of the GeoGebra in exercises on tangencies of a sphere and a cone: two examples. Transformación, [S. l.], v. 14, n. 2, p. 226‐235, 2024. Disponível em: https://transformacion.reduc.edu.cu/index.php/transformacion/article/view/195. Acesso em: 19 sep. 2025.