# Approximation of periodic analytic functions by Fejer sums

Author
Donbas State Pedagogical University, Slov’yansk, Ukraine; Donbas State Engineering Academy, Kramatorsk, Ukraine
Abstract
For upper bounds of the deviations of Fejer sums taken over classes of periodic functions that admit analytic extensions to a fixed strip of the complex plane, we obtain asymptotic equalities. In certain cases, these equalities give a solution of the corresponding Kolmogorov-Nikolsky problem.
Keywords
asymptotic equality; analytic functions; Fejer sums; de la Vallee Poussin sums; Poisson kernel
DOI
doi:10.15330/ms.47.2.196-201
Reference
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Pages
196-201
Volume
47
Issue
2
Year
2017
Journal
Matematychni Studii
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