The aim of this paper is to study the following second order system of difference equations $$\begin{array}{} x_{n+1} = f(y_{n},y_{n-1}),\quad y_{n+1} = g(x_{n},x_{n-1}) \end{array}$$ wheren∈ ℕ0, the initial valuesx−1,x0,y−1andy0are positive real numbers, the functionsf,g: (0, +∞)2→ (0, +∞) are continuous and homogeneous of degree zero. In this study, we establish results on local stability of the unique equilibrium point and to deal with the global attractivity, and so the global stability, some general convergence theorems are provided. Necessary and sufficient conditions on existence of prime period two solutions of our system are given. Also, a result on oscillatory solutions is proved. As applications of the obtained results, concrete models of systems of difference equations defined by homogeneous functions of degree zero are investigated. Our system generalize some existing works in the literature and our results can be applied to study new models of systems of difference equations. For interested readers, we left in the conclusion as open problems two more general systems of higher order defined by homogenous functions of degree zero.
7 December 2016 in Mathematical Methods in the Applied Sciences
We show that the three-dimensional system of difference equations x(n+1) = ax(n)z(n-1)/z(n)-beta + gamma,gamma(n+1) =by(n)x(n-1)/x(n)-gamma + alpha, Z(n+1) = cz(n)y(n-1)/y(n)-alpha + beta, n is an element of N-0, where the parameters a, b, c, alpha, beta, gamma and the initial conditions x(-i), y(-i), z(-i), i is an element of {0,1}, are nonzero real numbers, can be solved. Using the obtained formulas, we determine the asymptotic behavior of solutions and give conditions for which periodic solutions exist. Some numerical examples are given to demonstrate the theoretical results.