Oscillation Theorems for Second Order Nonlinear Neutral Type Difference Equations with Positive and Negative Coefficients

In this paper, the authors using two inequalities and Ricatti type transformation obtained some new oscillation results for the second order nonlinear neutral type difference equations of the form ∆(an∆(xn + cnxn−k)) + pnf(xn+1−l)− qng(xn+1−m) = 0, and ∆(an∆(xn − cnxn−k)) + pnf(xn+1−l)− qng(xn+1−m) = 0. The obtained results improve, extend and generalize some of the known results. Further examples are provided to illustrate the importance of the main results. Mathematics Subject Classification (2010): 39A10, 39A21.