Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)2022-03-142022-03-14https://noesis.uis.edu.co/handle/20.500.14071/7143        In this note we present some sufficient conditions for the global existence of all solutions of the bidimensional system x’=α (y) – β(y)f(x), y’=-α(t)g(x), which contains the classical Lienard's equation.    application/binaryinfo:eu-repo/semantics/articlehttp://purl.org/coar/access_right/c_abf2info:eu-repo/semantics/openAccessAtribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)