Oscillation of higher order differential equations

Differential equations has been studied for a long time and its applications are avaliable in many scientific branches. In many years there has been much research activity concerning the oscillaton of delay differential equations. In the first chapter of the thesis, we tread some results given for differential equations in the literature. In the second chapter, general defination and some theorems for oscillations of delay differential equations are given. In the third chapter, oscillation of higher order nonlinear delay differential equations with oscillatory coefficientshave been examined. In the fourth chapter, where our original results are given, the higher order nonlinear neutral type functional differential equationis considered and sufficient conditions for oscillation of bounded solutions of this equation are given.Keywords and Phrases: Differential equations, oscillation, nonoscillation, neutral, delay.