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HYPERSTABILITY OF GENERALISED LINEAR FUNCTIONAL EQUATIONS IN SEVERAL VARIABLES

Published online by Cambridge University Press:  18 June 2020

THEERAYOOT PHOCHAI
Affiliation:
Department of Mathematics, Faculty of Science, Khon Kaen University, Khon Kaen40002, Thailand email theerayoot.p@kkumail.com
SATIT SAEJUNG*
Affiliation:
Department of Mathematics, Faculty of Science, Khon Kaen University, Khon Kaen40002, Thailand Research Center for Environmental and Hazardous Substance Management (EHSM), Khon Kaen University, Khon Kaen40002, Thailand Center of Excellence on Hazardous Substance Management (HSM), Patumwan, Bangkok10330, Thailand email saejung@kku.ac.th

Abstract

Zhang [‘On hyperstability of generalised linear functional equations in several variables’, Bull. Aust. Math. Soc.92 (2015), 259–267] proved a hyperstability result for generalised linear functional equations in several variables by using Brzdęk’s fixed point theorem. We complete and extend Zhang’s result. We illustrate our results for general linear equations in two variables and Fréchet equations.

Type
Research Article
Copyright
© 2020 Australian Mathematical Publishing Association Inc.

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Footnotes

This work is supported by a research grant from the Faculty of Science, Khon Kaen University. The second author is also supported by the Thailand Research Fund and Khon Kaen University under grant RSA6280002.

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