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Ulyanov inequalities for the mixed moduli of smoothness in mixed metrics

  • Boris V. Simonov and Ainur A. Jumabayeva EMAIL logo
Published/Copyright: August 3, 2024
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Abstract

In this paper, mixed moduli of smoothness of functions of two variables are studied. We prove Ulyanov-type inequalities between mixed moduli of smoothness of positive orders in different metrics. Estimates for the mixed moduli of smoothness of the derivative of a function are also obtained in terms of the mixed moduli of smoothness of the function itself.

MSC 2020: 26B05; 41A17; 46E35

Funding statement: This research was partially funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP14870758).

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Received: 2023-07-06
Revised: 2024-02-26
Accepted: 2024-03-04
Published Online: 2024-08-03
Published in Print: 2025-02-01

© 2024 Walter de Gruyter GmbH, Berlin/Boston

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