摘要:We establish new comparison theorems, to offer criteria for all nonoscillatory solutions of the third-order functional differential equation [ r ( t ) [ x ′ ( t ) ] γ ] ″ + p ( t ) x β ( τ ( t ) ) = 0 tend to zero. We consider both delay and advanced case of studied equation. The results obtained essentially improve and complement earlier ones. MSC:34K11, 34C10.