Positive Solutions of Difference Equations with Two-Point Right Focal Boundary Conditions

We consider the following boundary value problem: y1.nyp DnysF k, y,Dy, . . . , Dny1 y., nG2, 0FkFN, Di y 0. s0, 0FiFpy1, D i y Nq1.s0, pFiFny1, where 1FpFny1 is fixed. Using a fixed point theorem for operators on a cone, we develop criteria for the existence of two positive solutions of the boundary value problem. In addition, upper and lower bounds for these positive solutions are established for special cases. We also include several examples to dwell upon the importance of the results obtained.