Oscillation of Certain Second-Order Sub-Half-Linear Neutral Impulsive Differential Equations

By introducing auxiliary functions, we investigate the oscillation of a class of second-order sub-half-linear neutral impulsive differential equations of the form [r(t)phi(beta)(z'(t))]' + p(t)phi(alpha)(x(sigma(t))) = 0, t not equal theta(k), Delta phi(beta)(z'(t))vertical bar t=theta(k) + q(k)phi(alpha)(x(sigma(theta(k)))) = 0, Delta x(t)vertical bar t=theta(k) = 0, where beta > alpha > 0, z(t) = x(t) + lambda(t)x(tau(t)). Several oscillation criteria for the above equation are established in both the case 0 <= lambda(t) <= 1 and the case -1 < -mu <= lambda(t) <= 0, which generalize and complement some existing results in the literature. Two examples are also given to illustrate the effect of impulses on the oscillatory behavior of solutions to the equation.