Journal of the Chungcheong Mathematical Society (충청수학회지)

The Chungcheong Mathematical Society (충청수학회)
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APPROXIMATION OF ALMOST EULER-LAGRANGE QUADRATIC MAPPINGS BY QUADRATIC MAPPINGS

  • John Michael Rassias (Pedagogical Department E.E. National and Capodistrian University of Athens) ;
  • Hark-Mahn Kim (Department of Mathematics Chungnam National University) ;
  • Eunyoung Son (Department of Mathematics Chungnam National University)
  • Received : 2024.03.05
  • Accepted : 2024.05.08
  • Published : 2024.05.31
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Abstract

For any fixed integers k, l with kl(l - 1) ≠ 0, we establish the generalized Hyers-Ulam stability of an Euler-Lagrange quadratic functional equation f(kx + ly) + f(kx - ly) + 2(l - 1)[k2f(x) - lf(y)] = l[f(kx + y) + f(kx - y)] in normed spaces and in non-Archimedean spaces, respectively.

Keywords

Acknowledgement

This work was supported by research fund of Chungnam National University.

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