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arXiv · 1307.0638

Hyers--Ulam stability of derivations and linear functions

Zoltán Boros·Eszter Gselmann
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Abstract

In this paper the following implication is verified for certain basic algebraic curves: if the additive real function $f$ approximately (i.e., with a bounded error) satisfies the derivation rule along the graph of the algebraic curve in consideration, then $f$ can be represented as the sum of a derivation and a linear function. When, instead of the additivity of $f$, it is assumed that, in addition, the Cauchy difference of $f$ is bounded, a stability theorem is obtained for such characterizations of derivations.

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Zoltán Boros, Eszter Gselmann. 2013-07-02. Hyers--Ulam stability of derivations and linear functions. https://doi.org/10.1007/s00010-010-0026-1

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