On Best Polynomial Approximations in L2

被引：0

作者：

S. B. Vakarchuk

机构：

[1] Customs Academy of the Ukraine,

来源：

Mathematical Notes | 2001年 / 70卷

关键词：

best polynomial approximation; exact constants in Jackson-type inequalities; space of 2π-periodic measurable square-integrable functions; modulus of smoothness of ; th order;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

For the τ-moduli of smoothness of mth order, we calculate exact constants in Jackson-type inequalities. We also obtain the exact values of the n-widths of classes of functions whose rth derivatives are characterized by τ-moduli of smoothness majorized by functions satisfying certain constraints. We present an example of the majorant for which all the stated requirements are satisfied.

引用

页码：300 / 310

页数：10

共 9 条

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