Journal of applied mathematics & informatics

The Korean Society for Computational and Applied Mathematics (한국전산응용수학회)
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APPROXIMATION OF DRYGAS FUNCTIONAL EQUATION IN QUASI-BANACH SPACE

  • RAVINDER KUMAR SHARMA (School of Mathematics, Thapar Institute of Engineering and Technology) ;
  • SUMIT CHANDOK (School of Mathematics, Thapar Institute of Engineering and Technology)
  • Received : 2021.03.14
  • Accepted : 2022.12.26
  • Published : 2023.05.30
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Abstract

In this paper, we investigate the Hyers-Ulam-Rassias stability for a Drygas functional equation g(u + v) + g(u - v) = 2g(u) + g(v) + g(-v) in the setting of quasi-Banach space using fixed point approach. Also, we give general results on hyperstability of a Drygas functional equation. The results obtain in this paper extend various previously known results in the setting of quasi-Banach space. Some examples are also illustrated.

Keywords

Acknowledgement

The authors are thankful to the learned referees for their valuable suggestions.

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