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Demonstratio Mathematica

Editor-in-Chief: Vetro, Calogero

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CiteScore 2018: 0.47
SCImago Journal Rank (SJR) 2018: 0.265
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Volume 51, Issue 1


On trigonometric approximation of functions in the Lq norm

Ram N. Mohapatra / Bogdan Szal
  • Corresponding author
  • University of Zielona Góra, Faculty of Mathematics, Computer Science and Econometrics, 65-516 Zielona Góra, ul. Szafrana 4a, Poland
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Published Online: 2018-03-21 | DOI: https://doi.org/10.1515/dema-2018-0004


In this paper we obtain a degree of approximation of functions in Lq by operators associated with their Fourier series using integral modulus of continuity. These results generalize many known results and are proved under less stringent conditions on the infinite matrix.

Keywords: class Lip (β; q); trigonometric approximation; Lq norm

MSC 2010: 42A10; 41A25


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About the article

Received: 2017-08-25

Accepted: 2018-02-23

Published Online: 2018-03-21

Citation Information: Demonstratio Mathematica, Volume 51, Issue 1, Pages 17–26, ISSN (Online) 2391-4661, DOI: https://doi.org/10.1515/dema-2018-0004.

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© 2018 Bogdan Szal and Ram N. Mohapatra. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License. BY-NC-ND 4.0

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