Fixed Point Theory and Applications
Volume 2008 (2008), Article ID 945010, 7 pages
doi:10.1155/2008/945010
A fixed point approach to the stability of a functional equation of the spiral of Theodorus
Soon-Mo Jung1
and John Michael Rassias2
1Mathematics Section, College of Science and Technology, Hong-Ik University, 339-701 Chochiwon, South Korea
2Mathematics Section, Pedagogical Department, National and Capodistrian University of Athens, 4 Agamemnonos Street, Aghia Paraskevi, Attikis, 15342 Athens, Greece
Abstract
Cădariu and Radu applied the fixed point method to the investigation of Cauchy and Jensen functional equations. In this paper, we adopt the idea of Cădariu and Radu to prove the stability of a functional equation of the spiral of Theodorus, f(x+1)=(1+i/x+1)f(x).