On a Generalized Drygas Functional Equation and its Approximate Solutions in 2-Banach Spaces


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Authors: M. E. HRYROU AND S. KABBAJ

DOI: 10.46793/KgJMat2305.801H

Abstract:

In this paper, we introduce and solve the following generalized Drygas functional equation

f (x +  ky ) + f (x −  ky ) = 2f (x ) + k2f (y ) + k2f (− y ),
where k . Also, we discuss some stability and hyperstability results for the considered equation in 2-Banach spaces by using the fixed point approach.

Keywords:

Stability, hyperstability, Drygas functional equation, fixed point method, 2-Banach space.



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