Best approximations and widths of some classes of convolutions in L-2

被引：0

作者：

Tukhliev, K. ^{[1
]}

机构：

[1] Khudjand State Univ, Khudjand 735700, Tajikistan

来源：

TRUDY INSTITUTA MATEMATIKI I MEKHANIKI URO RAN | 2016年 / 22卷 / 04期

关键词：

best approximation; periodic function; trigonometric polynomial; modulus of continuity of mth order; n-widths;

D O I：

10.21538/0134-4889-2016-22-4-284-294

中图分类号：

O29 [应用数学];

学科分类号：

070104 ;

摘要：

We find tight upper bounds for the best approximations by trigonometric polynomials of certain classes of periodic functions representable as convolutions with structural characteristics defined by various modifications of m-th order moduli of continuity in the metric of L-2. We also find exact values for the n-widths of convolution classes given by such smoothness characteristics.

引用

页码：284 / 294

页数：11

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