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$K$-functionals and extreme problems of the theory of approximation for classes of analytic functions in the circle. I

УДК 517.5 Based on the Hadamard composition in the Hardy, Bergman and Gvaradze Banach spaces of functions analytic in the unit circle, we consider a generalization of the $K$-functional.&nbsp;In solving some extreme problems of the theory of approximation in the complex plane, we obtain cert...

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Bibliographic Details
Date:	2022
Main Authors:	Vakarchuk, S. B., Vakarchuk, M. B., Вакарчук, С. Б., Вакарчук, М. Б.
Format:	Article
Language:	Ukrainian
Published:	Institute of Mathematics, NAS of Ukraine 2022
Online Access:	https://umj.imath.kiev.ua/index.php/umj/article/view/6980
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Journal Title:	Ukrains’kyi Matematychnyi Zhurnal
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