# Periodic solutions of fourth-order delay differential equation

Document Type : Research Paper

Author

SRM UNIVERSITY,

Abstract

In this paper the periodic solutions of fourth order delay differential equation of the form $\ddddot{x}(t)+a\dddot{x}(t)+f(\ddot{x}(t-\tau(t)))+g(\dot{x}(t-\tau(t)))+h({x}(t-\tau(t)))=p(t)$  is investigated. Some new positive periodic criteria are given.

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### History

• Receive Date: 28 December 2013
• Revise Date: 29 April 2015
• Accept Date: 03 February 2014