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http://dx.doi.org/10.7468/jksmeb.2012.19.2.193

APPROXIMATE PEXIDERIZED EXPONENTIAL TYPE FUNCTIONS  

Lee, Young-Whan (Department of Computer Hacking and Information Security, College of Natural Science, Daejeon University)
Publication Information
The Pure and Applied Mathematics / v.19, no.2, 2012 , pp. 193-198 More about this Journal
Abstract
We show that every unbounded approximate Pexiderized exponential type function has the exponential type. That is, we obtain the superstability of the Pexiderized exponential type functional equation $$f(x+y)=e(x,y)g(x)h(y)$$. From this result, we have the superstability of the exponential functional equation $$f(x+y)=f(x)f(y)$$.
Keywords
functional equation; stability; superstability; gamma and beta functional equation; Cauchy functional equation; exponential functional equation;
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