Electronic Journal of Qualitative Theory of Differential Equations (Jun 2010)
Effect of nonlinear perturbations on second order linear nonoscillatory differential equations
Abstract
The aim of this paper is to show that any second order nonoscillatory linear differential equation can be converted into an oscillating system by applying a sufficiently large nonlinear perturbation. This can be achieved through a detailed analysis of possible nonoscillatory solutions of the perturbed differential equation which may exist when the perturbation is sufficiently small. As a consequence the class of oscillation-generating perturbations is determined precisely with respect to the original nonoscillatory linear equation.