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
收藏
页码：284 / 294
页数：11
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