A Sharp Inequality for a Trigonometric Sum

被引:0
|
作者
Alzer, Horst [1 ]
Koumandos, Stamatis [1 ]
机构
[1] Univ Cyprus, Dept Math & Stat, CY-1678 Nicosia, Cyprus
关键词
Inequalities; sine sums; cosine sums; 2; VARIABLES; POLYNOMIALS; SERIES; FOURIER;
D O I
10.1007/s00009-012-0188-2
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We prove that the inequality -1/2 <= Sigma(n)(k=1) (COS(2kx)/2k - 1) + sin((2k - 1)x)/2k) holds for all natural numbers n and real numbers x with x epsilon [0, pi]. The sign of equality is valid if and only if n = 1 and x = pi/2.
引用
收藏
页码:313 / 320
页数:8
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