Oscillation and Nonoscillation for Second Order Linear Impulsive Differential Equations*

We study the oscillation and nonoscillation for the second order linear impulsive differential equation u0 syp t.u, where p t. is an impulsive function defined by p t.s `ns1 and tytn., and we establish a necessary and sufficient condition for oscillation or nonoscillation.of the equation u0 syp t.u. We give some sufficient conditions for the oscillation and nonoscillation in two particular cases.