Oscillation criteria for second order nonlinear dynamic equations with impulses

We investigate the oscillatory behavior of the second order nonlinear dynamic equation ` a(x) ́∆ (t) + q(t)x(t) = 0, the forced dynamic equation ` a(x) ́∆ (t) + q(t)x(t) = e(t) and the forced-perturbed dynamic equation ` a(x) ́∆ (t) + q(t)x(t) = e(t) + p(t)x (t). The obtained results are new and not only extend the known results appeared in the literature, but they also improve and unify the known oscillation criteria for corresponding half-linear and nonlinear differential and difference equations.