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ADDITIVE FUNCTIONAL INEQUALITIES AND DERIVATIONS ON HILBERT C*-MODULES

Published online by Cambridge University Press:  05 March 2013

FRIDOUN MORADLOU*
Affiliation:
Department of Mathematics, Sahand University of Technology, Tabriz, Iran e-mail: moradlou@sut.ac.ir
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Abstract

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In this paper we investigate the following functional inequality

$ \begin{eqnarray*} \| f(x-y-z) - f(x-y+z) + f(y) +f(z)\| \leq \|f(x+y-z) - f(x)\| \end{eqnarray*}$
in Banach spaces, and employing the above inequality we prove the generalized Hyers–Ulam stability of derivations in Hilbert C*-modules.

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 2013

References

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