Approximation of $\bar {\psi} - integrals$−integrals of periodic functions by Fourier sums (small smoothness). Iof periodic functions by Fourier sums (small smoothness). I

We investigate the rate of convergence of Fourier series on the classes $L^{\bar {\psi} } \text{N}$ in the uniform and integral metrics. The results obtained are extended to the case where the classes $L^{\bar {\psi} } \text{N}$ are the classes of convolutions of functions from $\text{N}$ with...

Full description

Saved in:
Bibliographic Details
Date:1998
Main Authors: Stepanets, O. I., Степанец, А. И.
Format: Article
Language:Russian
English
Published: Institute of Mathematics, NAS of Ukraine 1998
Online Access:https://umj.imath.kiev.ua/index.php/umj/article/view/4961
Tags: Add Tag
No Tags, Be the first to tag this record!
Journal Title:Ukrains’kyi Matematychnyi Zhurnal
Download file: Pdf

Institution

Ukrains’kyi Matematychnyi Zhurnal
Description
Summary:We investigate the rate of convergence of Fourier series on the classes $L^{\bar {\psi} } \text{N}$ in the uniform and integral metrics. The results obtained are extended to the case where the classes $L^{\bar {\psi} } \text{N}$ are the classes of convolutions of functions from $\text{N}$ with kernels with slowly decreasing coefficients. In particular, we obtain asymptotic equalities for the upper bounds of deviations of the Fourier sums on the sets $L^{\bar {\psi} } \text{N}$ which are solutions of the Kolmogorov-Nikol’skii problem. In addition, we establish an analog of the well-known Lebesgue inequality.