On the stability of the squares of some functional equations

Zenon Moszner

Abstract


We consider the stability, the superstability and the inverse stability of the functional equations with squares of Cauchy’s, of Jensen’s and of isometry equations and the stability in Ulam-Hyers sense of the alternation of functional equations and of the equation of isometry.

Keywords


Stability, superstability, inverse stability, isometry

Mathematics Subject Classification (2010)


39B82; 39B62

References


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