A fixed point approach to the hyperstability of Drygas functional equation in metric spaces
Abstract
Piszczek and Szczawi´ nska proved the hyperstability of the Drygas functional equation in Banach spaces. Using the fixed point method, we prove the hyperstability of the Drygas functional equation f(x+y)+ f(x−y) =2f(x)+ f(y)+ f(−y), in the class of functions from a commutative group into a commutative complete metric group.
Copyright © 2014 Mohamed Sirouni, Samir Kabbaj. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Cite this article
M. Sirouni, S. Kabbaj, A fixed point approach to the hyperstability of Drygas functional equation in metric spaces, J. Math. Comput. Sci. 4 (2014), 705–715.
BibTeX
@article{Sirouni2014,
author = {Sirouni, Mohamed and Kabbaj, Samir},
title = {A fixed point approach to the hyperstability of Drygas functional equation in metric spaces},
journal = {J. Math. Comput. Sci.},
volume = {4},
year = {2014},
pages = {705--715},
doi = {}
}