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arXiv · 1901.03957

Richard's inequality, Cauchy-Schwarz's inequality and approximate solutions of Sincov's equation

Włodzimierz Fechner
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Abstract

We observe a connection between Cauchy-Schwarz' and Richard's inequalities in inner product spaces and a Ulam-type stability problem for multiplicative Sincov's functional equation. We prove that this equation is super-stable for unbounded mappings, i.e. every unbounded approximate solution is an exact solution.

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Włodzimierz Fechner. 2019-01-13. Richard's inequality, Cauchy-Schwarz's inequality and approximate solutions of Sincov's equation. https://doi.org/10.1090/proc%2F14543

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