OSCILLATION OF SECOND ORDER NEUTRAL DIFFERENTIAL EQUATIONS WITH MIXED NEUTRAL TERM

This paper deals with the following second order neutral differential equation of the form (r(t)z ' (t)) ' + q(t)x(σ(t)) = 0, t ≥ t0 ≥ 0 where z(t) = x(t)+a(t)x(t−τ)+b(t)x(t+δ), and R ∞ t0 1 r(t) dt = ∞. We obtain some new oscillation criteria which extend some known results. Examples are presented to illustrate the main results.