APPROXIMATE GENERALIZED EXPONENTIAL FUNCTIONS

• Journal title : Honam Mathematical Journal
• Volume 31, Issue 3,  2009, pp.451-462
• Publisher : The Honam Mathematical Society
• DOI : 10.5831/HMJ.2009.31.3.451
Title & Authors
APPROXIMATE GENERALIZED EXPONENTIAL FUNCTIONS
Lee, Eun-Hwi;

Abstract
In this paper we prove the superstability of a generalized exponential functional equation $\small{f(x+y)=a^{2xy-1}g(x)f(y)}$. It is a generalization of the superstability theorem for the exponential functional equation proved by Baker. Also we investigate the stability of this functional equation in the following form : $\small{{\frac{1}{1+{\delta}}}{\leq}{\frac{f(x+y)}{a^{2xy-1}g(x)f(y)}}{\leq}1+{\delta}}$.
Keywords
and phrases Exponential functional equation;Stability of functional equation;Superstability;
Language
English
Cited by
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