The authors study the second-order impulsive ordinary differential equation
where , and satisfies the sign condition for all and the growth condition for all where , for and . The impulses
are supposed to satisfy and
where , , and are positive real numbers. Sufficient conditions for the oscillation of equation (1) are established. One of the typical results is the following theorem:
and there exists a positive integer such that for . If
hold for some and
then every solution of equation (1) is oscillatory.