TY - JOUR AU - Adeyanju, Adetunji PY - 2023/05/16 Y2 - 2024/03/29 TI - On uniform-ultimate boundedness and periodicity results of solutions to certain second order non-linear vector differential equations JF - Proyecciones (Antofagasta, On line) JA - Proyecciones (Antofagasta, On line) VL - 42 IS - 3 SE - DO - 10.22199/issn.0717-6279-5421 UR - https://www.revistaproyecciones.cl/index.php/proyecciones/article/view/5421 SP - 757-773 AB - <p>In this paper, we employ the second method of Lyapunov to examine sufficient conditions for the uniform-ultimate boundedness of solutions and existence of at least one periodic solution to the following second order vector differential equation:</p><p>Ẍ+ F(X, Ẋ ) Ẋ + H(X) = P(t, X, Ẋ ),</p><p>when the non-linear term H(X) is: (i) differentiable, (ii) non-necessarily differentiable. The results contain in this paper are new and complement related ones in the literature.</p> ER -