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Best Polynomial Approximations in $L_2$ and Widths of Some Classes of Functions

We obtain the exact values of extremal characteristics of a special form that connect the best polynomial approximations of functions $f(x) ∈ L_2^r(r ∈ ℤ_{+})$ and expressions containing moduli of continuity of the $k$th order $ω_k(f^{(r)}, t)$. Using these exact values, we generalize the Taikov res...

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Bibliographic Details
Date:	2004
Main Authors:	Vakarchuk, S. B., Shchitov, A. N., Вакарчук, С. Б., Щитов, А. Н.
Format:	Article
Language:	Russian English
Published:	Institute of Mathematics, NAS of Ukraine 2004
Online Access:	https://umj.imath.kiev.ua/index.php/umj/article/view/3858
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Journal Title:	Ukrains’kyi Matematychnyi Zhurnal
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