Startseite Direct and inverse approximation theorems of functions in the Orlicz type spaces 𝓢M
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Direct and inverse approximation theorems of functions in the Orlicz type spaces 𝓢M

  • Stanislav Chaichenko EMAIL logo , Andrii Shidlich und Fahreddin Abdullayev
VerĂśffentlicht/Copyright: 22. Dezember 2019
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Abstract

In the Orlicz type spaces 𝓢M, we prove direct and inverse approximation theorems in terms of the best approximations of functions and moduli of smoothness of fractional order. We also show the equivalence between moduli of smoothness and Peetre K-functionals in the spaces 𝓢M.


This work was supported in part by the Ministry of Education and Science of Ukraine within the framework of the fundamental research No. 0118U003390 and the Kyrgyz-Turkish Manas University (Bishkek / Kyrgyz Republic), project No. KTMÜ-BAP-2018.FBE.05.


  1. Communicated by Tomasz Natkaniec

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Received: 2019-01-22
Accepted: 2019-04-18
Published Online: 2019-12-22
Published in Print: 2019-12-18

Š 2019 Mathematical Institute Slovak Academy of Sciences

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