Positive solutions of second-order delay differential equations with a damping term

In the paper, the existence of positive solutions is studied for the second-order delay differential equation with a damping term Rx.t/ C a.t/Px.t/ C b.t/x.h.t// D 0 using a comparison with the integro-differential equation Py.t/ C Z t t0 e􀀀 R t s a. /d b.s/y.h.s//ds D 0: Explicit non-oscillation criteria and comparison type results are derived.