Improved Comparison Theorems for the Oscillation of Even Order Delay Differential Equations and their Applications

Abstract In this work, only two independent conditions for the oscillation of all solutions of even-order delay differential equations in the non-canonical case are established. Using comparison techniques with first- and second-order delay differential equations, we obtain easy-to-apply criteria that improve previous results in the literature. In addition, we show the importance of our results by applying them to examples that have been frequently used in related works.