Nonlinear evolution equations for Riccati equation method

Nonlinear differential equations which are equations that can be used many areas such as chemistry, physics and biology. Application mathematics is interested in with exact solution of this equations and improving new solution methods.This thesis study consists of three chapters. In the first chapter, ordinary and partial differential equations and their classifications, nonlinear evolution equations and soliton theory in physics are given.In the second chapter, tanh and Riccati equation methods are introduced in order to find exact solutions of nonlinear evolution equations and some applications of these methods are given.In the third chapter, improved tanh method, which is developed recently, is given and applications of this method is shown for nonlinear evolution equations systems.