Oscillation criteria for third-order nonlinear functional differential equations

In this work, we are concerned with oscillation of third-order nonlinear functional differential equations of the form (r2(t)(r1(t)y′)′)′+p(t)y′+q(t)f(y(g(t)))=0. By using a Riccati type transformation and integral averaging technique, we establish some new sufficient conditions under which every solution y(t)y(t) either oscillates or converges to zero as t→∞t→∞.Unlike ones from the known works in the literature, our results are applicable to nonlinear functional differential equations of the above form when f(u)=|u|α−1uf(u)=|u|α−1u, α>0α>0.