Journal of Inequalities and Applications 
Volume 2 (1998), Issue 3, Pages 235-253
doi:10.1155/S1025583498000149

On Ozeki’s inequality

Saichi Izumino,1 Hideo Mori,2 and Yuki Seo3

 1Faculty of Education, Toyama University, Gofuku, Toyama 930, Japan
2Department of Mathematics, Osaka Kyoiku University, Kashiwara, Osaka 582, Japan
3Tennoji Branch, Senior Highschool, Osaka Kyoiku University, Tennoji, Osaka 543, Japan
Received 6 April 1997; Revised 30 June 1997

Abstract

We shall obtain the best bound in Ozeki’s inequality which estimates the difference of Cauchy’s inequality. We also give an operator version of Ozeki’s inequality which extends an inequality on the variance of an operator.