ON A ONE-PARAMETER CLASS OF COSINE POLYNOMIALS

被引：0

作者：

Alzer, Horst ^{[1
]}

Kwong, Man Kam ^{[2
]}

机构：

[1] Morsbacher Str 10, D-51545 Waldbrol, Germany

[2] Hong Kong Polytech Univ, Dept Appl Math, Hong Kong, Peoples R China

来源：

MOSCOW MATHEMATICAL JOURNAL | 2023年 / 23卷 / 01期

关键词：

Cosine polynomials; inequalities; SERIES;

D O I：

10.17323/1609-4514-2023-23-1-1-9

中图分类号：

O29 [应用数学];

学科分类号：

070104 ;

摘要：

We prove: Let a >= 0 be a real number. For any integer n >= 2 and any real x is an element of (0, pi), we have 1 + cos(x) + Sigma(n)(k=2) cos(kx)/k+a > 1/(a+2)(a+3). The lower bound is sharp. This extends a result of Brown and Koumandos, who proved the inequality for the special case a = 0.

引用

页码：1 / 9

页数：9

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