On approximation of functions from the class $L^{\psi}_{\beta, 1}$ by the Abel-Poisson integrals in the integral metric

In the paper, we investigate an asymptotic behavior of the sharp upper bounds in the integral metric of deviations of the Abel-Poisson integrals from functions from the class $L^{\psi}_{\beta, 1}$. The Abel-Poisson integrals are solutions of the partial differential equations of elliptic type with c...

Full description

Bibliographic Details
Main Authors: T.V. Zhyhallo, Yu.I. Kharkevych
Format: Article
Language:English
Published: Vasyl Stefanyk Precarpathian National University 2022-06-01
Series:Karpatsʹkì Matematičnì Publìkacìï
Subjects:
Online Access:https://journals.pnu.edu.ua/index.php/cmp/article/view/5678
_version_ 1797205808549724160
author T.V. Zhyhallo
Yu.I. Kharkevych
author_facet T.V. Zhyhallo
Yu.I. Kharkevych
author_sort T.V. Zhyhallo
collection DOAJ
description In the paper, we investigate an asymptotic behavior of the sharp upper bounds in the integral metric of deviations of the Abel-Poisson integrals from functions from the class $L^{\psi}_{\beta, 1}$. The Abel-Poisson integrals are solutions of the partial differential equations of elliptic type with corresponding boundary conditions, and they play an important role in applied problems. The approximative properties of the Abel-Poisson integrals on different classes of differentiable functions were studied in a number of papers. Nevertheless, a problem on the respective approximation on the classes $L^{\psi}_{\beta,1}$ in the metric of the space $L$ remained unsolved. We managed to obtain the estimates for the values of approximation of $(\psi, \beta)$-differentiable functions from the unit ball of the space $L$ by the Abel-Poisson integrals. In some cases, we also write down asymptotic equalities for these quantities, that is we solve the Kolmogorov-Nikol'skii problem for the the Abel-Poisson integrals on the classes $L^{\psi}_{\beta,1}$ in the integral metric.
first_indexed 2024-04-24T08:57:00Z
format Article
id doaj.art-db5e251b7112432b8c5a8a1af7ad39c0
institution Directory Open Access Journal
issn 2075-9827
2313-0210
language English
last_indexed 2024-04-24T08:57:00Z
publishDate 2022-06-01
publisher Vasyl Stefanyk Precarpathian National University
record_format Article
series Karpatsʹkì Matematičnì Publìkacìï
spelling doaj.art-db5e251b7112432b8c5a8a1af7ad39c02024-04-16T07:10:59ZengVasyl Stefanyk Precarpathian National UniversityKarpatsʹkì Matematičnì Publìkacìï2075-98272313-02102022-06-0114122322910.15330/cmp.14.1.223-2294910On approximation of functions from the class $L^{\psi}_{\beta, 1}$ by the Abel-Poisson integrals in the integral metricT.V. Zhyhallo0Yu.I. Kharkevych1Lesya Ukrainka Volyn National University, 13 Voli avenue, 43025, Lutsk, UkraineLesya Ukrainka Volyn National University, 13 Voli avenue, 43025, Lutsk, UkraineIn the paper, we investigate an asymptotic behavior of the sharp upper bounds in the integral metric of deviations of the Abel-Poisson integrals from functions from the class $L^{\psi}_{\beta, 1}$. The Abel-Poisson integrals are solutions of the partial differential equations of elliptic type with corresponding boundary conditions, and they play an important role in applied problems. The approximative properties of the Abel-Poisson integrals on different classes of differentiable functions were studied in a number of papers. Nevertheless, a problem on the respective approximation on the classes $L^{\psi}_{\beta,1}$ in the metric of the space $L$ remained unsolved. We managed to obtain the estimates for the values of approximation of $(\psi, \beta)$-differentiable functions from the unit ball of the space $L$ by the Abel-Poisson integrals. In some cases, we also write down asymptotic equalities for these quantities, that is we solve the Kolmogorov-Nikol'skii problem for the the Abel-Poisson integrals on the classes $L^{\psi}_{\beta,1}$ in the integral metric.https://journals.pnu.edu.ua/index.php/cmp/article/view/5678kolmogorov-nikol'skii problemabel-poisson integral$(\psi, \beta)$-differentiable functionasymptotic equalityintegral metric
spellingShingle T.V. Zhyhallo
Yu.I. Kharkevych
On approximation of functions from the class $L^{\psi}_{\beta, 1}$ by the Abel-Poisson integrals in the integral metric
Karpatsʹkì Matematičnì Publìkacìï
kolmogorov-nikol'skii problem
abel-poisson integral
$(\psi, \beta)$-differentiable function
asymptotic equality
integral metric
title On approximation of functions from the class $L^{\psi}_{\beta, 1}$ by the Abel-Poisson integrals in the integral metric
title_full On approximation of functions from the class $L^{\psi}_{\beta, 1}$ by the Abel-Poisson integrals in the integral metric
title_fullStr On approximation of functions from the class $L^{\psi}_{\beta, 1}$ by the Abel-Poisson integrals in the integral metric
title_full_unstemmed On approximation of functions from the class $L^{\psi}_{\beta, 1}$ by the Abel-Poisson integrals in the integral metric
title_short On approximation of functions from the class $L^{\psi}_{\beta, 1}$ by the Abel-Poisson integrals in the integral metric
title_sort on approximation of functions from the class l psi beta 1 by the abel poisson integrals in the integral metric
topic kolmogorov-nikol'skii problem
abel-poisson integral
$(\psi, \beta)$-differentiable function
asymptotic equality
integral metric
url https://journals.pnu.edu.ua/index.php/cmp/article/view/5678
work_keys_str_mv AT tvzhyhallo onapproximationoffunctionsfromtheclasslpsibeta1bytheabelpoissonintegralsintheintegralmetric
AT yuikharkevych onapproximationoffunctionsfromtheclasslpsibeta1bytheabelpoissonintegralsintheintegralmetric