Kneser solutions of fourth-order trinomial delay differential equations

The objective of this paper is to study asymptotic properties of the fourth-order linear trinomial delay differential equation equation(EE)y(4)(t)+p(t)y′(t)+q(t)y(τ(t))=0.y(4)(t)+p(t)y′(t)+q(t)y(τ(t))=0. Applying suitable comparison principles, we present new criteria for all solutions of (E)(E) to be Kneser ones. Obtained results essentially simplify the examination of the studied equations.