Classifications and existence of positive solutions of higher-order nonlinear neutral differential equations

摘要

In this paper, necessary and sufficient conditions for the existence and classification of positive solutions of the higher order neutral differential equationr(t)x(t)−∑i=1mPi(t)x(t−τi)(n−1)′+ft,x(t−σ1),…,x(t−σl)=0are obtained, where Pi(t)⩾0, i=1,…,m, f(t,μ1,…,μl)∈C([t0,∞)×Rl,R).