Fixed Point Theory and Applications
Volume 2009 (2009), Article ID 192872, 10 pages
doi:10.1155/2009/192872
Research Article

A Generalization of Kannan's Fixed Point Theorem

Yusuke Enjouji, Masato Nakanishi, and Tomonari Suzuki

Department of Mathematics, Kyushu Institute of Technology, Tobata, Kitakyushu 804-8550, Japan

Received 22 December 2008; Accepted 23 March 2009

Academic Editor: Jerzy Jezierski

Copyright © 2009 Yusuke Enjouji et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In order to observe the condition of Kannan mappings, we prove a generalization of Kannan's fixed point theorem. Our theorem involves constants and we obtain the best constants to ensure a fixed point.