TANGENT FUNCTION AS A SOLUTION OF A 3-DIMENSIONAL FUNCTIONAL EQUATION. Far East Journal of Mathematical Education, [S. l.], v. 25, p. 57–61, 2023. DOI: 10.17654/0973563123016. Disponível em: https://pphmjopenaccess.com/fejme/article/view/1137. Acesso em: 5 jan. 2026.