Existence and uniqueness of a periodic solution to a certain third-order neutral functional differential equation

[摘要] In this paper, by applying Mawhin's continuation theorem of the coincidence degree theory, some sufficient conditions for the existence and uniqueness of an \(\omega\)-periodic solution for the following third-order neutral functional differential equation are established \(\dfrac{d^{3}}{dt^{3}}\bigg ( x(t)-d(t)x\big (t-\delta(t)\big ) \bigg )+a(t)\ddot{x}(t)+b(t)f\big (t,\dot{x}(t)\big )+\sum_{i=1}^{n}c_{i}(t)g\big (t,x(t-\tau_{i}(t))\big )=e(t)\).Moreover, we present an example and a graph to demonstrate the validity of analytical conclusion.

[学科分类] 工程和技术（综合）

[关键词] Periodic solution;coincidence degree theory;generalized neutral operator;neutral differential equation.