Original Article
Kyungpook Mathematical Journal 2008; 48(2): 173-181
Published online June 23, 2008
Copyright © Kyungpook Mathematical Journal.
The Asymptotic Stability of $x_{n+1}-a^{2}x_{n-1}+bx_{n-k}=0$
Piyapong Niamsup1, Yongwimon Lenbury2
1Department of Mathematics, Faculty of Science, Chiangmai University, Chiangmai, 50200, Thailand
2Department of Mathematics, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
We give the necessary and sufficient conditions for the asymptotic stability of the linear delay difference equation $x_{n+1}-a^{2}x_{n-1}+bx_{n-k}=0,quad n=0,1,cdots$, where $a$ and $b$ are arbitrary real numbers and $k$ is a positive integer greater than 1. The obtained conditions are given in terms of parameters $a$ and $b$ of difference equations. The method of proof is based on arithematic of complex numbers as well as properties of analytic functions.
Keywords: the asymptotic stability, linear delay difference equation