A SIMPLE PROOF OF OPPENHEIM'S DOUBLE INEQUALITY RELATING TO THE COSINE AND SINE FUNCTIONS

被引：8

作者：

Qi, Feng ^{[1
]}

Luo, Qiu-Ming ^{[2
]}

Guo, Bai-Ni ^{[3
]}

机构：

[1] Inner Mongolia Univ Nationalities, Coll Math, Tongliao City 028043, Inner Mongolia, Peoples R China

[2] Chongqing Normal Univ, Dept Math, Chongqing 401331, Peoples R China

[3] Henan Polytech Univ, Sch Math & Informat, Jiaozuo City 454010, Henan Province, Peoples R China

来源：

JOURNAL OF MATHEMATICAL INEQUALITIES | 2012年 / 6卷 / 04期

关键词：

Simple proof; Oppenheim's double inequality; cosine function; sine function; monotonicity; JORDANS INEQUALITY;

D O I：

10.7153/jmi-06-63

中图分类号：

O29 [应用数学];

学科分类号：

070104 ;

摘要：

In the paper, the authors provide a simple proof of Oppenheim's double inequality relating to the cosine and sine functions. In passing, the authors survey this topic.

引用

页码：645 / 654

页数：10