Approximation of the function |sin x| s by the partial sums of the trigonmometric rational fourier series
https://doi.org/10.29235/1561-8323-2021-65-1-11-17
Abstract
In the present article, the approximation of the function |sin x| s by the partial sums of the rational trigonometric Fourier series is considered. An integral representation, uniform and point estimates for the above-mentioned approximation were obtained. Based on them, several special cases of the selection of poles were studied. In the case of the approximation by the partial sums of the polynomial trigonometric Fourier series, an asymptotic equality was found. A detailed study is made of a fixed number of geometrically different poles.
About the Authors
N. Yu. Kazlouskaya
Yanka Kupala State University of Grodno
Belarus
Belarus
Kazlouskaya Natallia Yu. – Postgraduate student
22, Azheshka Str., 230023, Grodna
Ya. A. Rovba
Yanka Kupala State University of Grodno
Belarus
Belarus
Rovba Yaugeni A. – D. Sc (Physics and Mathematics), Professor, Head of the Department
22, Azheshka Str., 230023, Grodna
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