A new type of Hyers-Ulam-Rassias stability for Drygas functional equation

Journal of Linear and Topological Algebra

مقاله 1، دوره 07، شماره 04، بهمن 2018، صفحه 251-260   

نوع مقاله: Research Paper

نویسندگان

M. Sirouni؛ M. ‎Almahalebi^* ؛ S. ‎Kabbaj

Department of Mathematics‎, ‎Faculty of Science‎, ‎Ibn Tofail University‎, ‎BP-14000‎, ‎Kenitra‎, ‎Morocco

چکیده

In this paper, we prove the generalized Hyers-Ulam-Rassias stability for the Drygas functional equation
$$f(x+y)+f(x-y)=2f(x)+f(y)+f(-y)$$ in Banach spaces by using the Brz\c{d}ek's fixed point theorem. Moreover, we give a general result on the hyperstability of this equation. Our results are improvements and generalizations of the main result of M. Piszczek and J. Szczawi'{n}ska [21].

کلیدواژه‌ها

Stability؛ hyperstability؛ Drygas functional equation؛ fixed point method؛ Banach space

مراجع

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