Consider the n-order neutral delay differential equation
dndtn[y(t)+P(t)y(t−τ)]+Q(t)y(t−σ)=0
where P,Q∈C[[t0,∞),ℝ] and the delays τ and σ are nonnegative real numbers. In this paper we
examined the oscillatory behavior of the solutions of the above equation using techniques which
allow the relaxation of the restrictions which has been introduced previously. We illustrate new
type of conditions which improve and extend known results, by relaxing hypotheses that P is
constant and Q is τ-periodic.