Research Article | Open Access

Volume 2012 |Article ID 892571 | https://doi.org/10.1155/2012/892571

E. M. Elsayed, M. M. El-Dessoky, Abdullah Alotaibi, "On the Solutions of a General System of Difference Equations", Discrete Dynamics in Nature and Society, vol. 2012, Article ID 892571, 12 pages, 2012. https://doi.org/10.1155/2012/892571

# On the Solutions of a General System of Difference Equations

Revised14 Feb 2012
Accepted16 Feb 2012
Published17 Apr 2012

#### Abstract

We deal with the solutions of the systems of the difference equations , , and , , , with a nonzero real numbers initial conditions. Also, the periodicity of the general system of variables will be considered.

#### 1. Introduction

In this paper, we deal with the solutions of the systems of the difference equations with a nonzero real numbers initial conditions. Also, the periodicity of the general system of variables will be considered.

Recently, there has been a great interest in studying nonlinear difference equations and systems (cf.  and the references therein). One of the reasons for this is a necessity for some techniques which can be used in investigating equations arising in mathematical models describing real-life situations in population biology, economy, probability theory, genetics, psychology, sociology, and so forth. Such equations also appear naturally as discrete analogues of differential equations which model various biological and economical systems.

Cinar  has obtained the positive solution of the difference equation system: Also, Çinar and Yalçinkaya  have obtained the positive solution of the difference equation system: Clark and Kulenović  have investigated the global stability properties and asymptotic behavior of solutions of the system Elabbasy et al.  have obtained the solution of particular cases of the following general system of difference equations: Elsayed  has obtained the solution of systems of difference equations of rational form.

Also, the behavior of the solutions of the following systems: has been studied by Elsayed .

Özban  has investigated the positive solutions of the system of rational difference equations: Özban  has investigated the solutions of the following system: Yang et al.  have investigated the positive solutions of the systems: Similar nonlinear systems of rational difference equations were investigated see .

Definition 1.1 (Periodicity). A sequence is said to be periodic with period if for all .

#### 2. Main Results

##### 2.1. The First System

In this section, we deal with the solutions of the system of the difference equations with a nonzero real numbers initial conditions and .

Theorem 2.1. Suppose that are solutions of system (2.1). Also, assume that the initial conditionsare arbitrary nonzero real numbers. Then all solutions of equation system (2.1) are eventually periodic with period .

Proof. From (2.1), we see that Hence, the proof is completed.

Numerical Example
In order to illustrate the results of this section and to support our theoretical discussions, we consider the following numerical example.

Example 2.2. Consider the difference system (2.1) with , , and the initial conditions , , , , , and . (See Figure 1).

##### 2.2. The Second System

In this section, we deal with the solutions of the system of the difference equations with a nonzero real numbers initial conditions and .

Theorem 2.3. Suppose that are solutions of system (2.3). Also, assume that the initial conditionsare arbitrary nonzero real numbers. Then all solutions of equation system (2.3) are eventually periodic with period .

Proof. From (2.3), we see that Hence, the proof is completed.

Example 2.4. Consider the difference system (2.3) with , , , and the initial conditions , , ,, , , , , and (See Figure 2).

Proposition 2.5. It is easy to see by induction that the following general system is periodic with period :

#### Acknowledgments

This article was funded by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah. The authors, therefore, acknowledge with thanks DSR technical and financial support.

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