Second Order Nonlinear Functional Differential Equations

This thesis is devoted to studying oscillation for several nonlinear second order functional differential equations. The oscillation criteria which this thesis builds generalizes and improves some known results.Chapter 1 introduces and summarizes the background and present situation and main contents of oscillation for functional differential equations.Chapter 2 studies oscillation for a class of second order nonlinear functional differential equation and obtains sufficient conditions of oscillation for the equation.In Chapter 3, the oscillation for a certain second order nonlinear neutral functional differential equation which contains stieltjes integral is studied.Chapter 4 investigates oscillation of another certain second order nonlinear neutral functional differential equation.By means of the averaging technique, chapter 5 obtains new interval oscillation criteria for second neutral functional differential equation. These results are different from most known ones in the sense that they are based on a sequence of subintervals nature.