Open Access

A pythagorean approach in Banach spaces

Journal of Inequalities and Applications20062006:94982

DOI: 10.1155/JIA/2006/94982

Received: 30 December 2003

Accepted: 4 May 2004

Published: 3 January 2006


Let be a Banach space and let be the unit sphere of . Parameters , , , and , where and are introduced and studied. The values of these parameters in the spaces and function spaces are estimated. Among the other results, we proved that a Banach space with , or is uniform nonsquare; and a Banach space with , or has uniform normal structure.


Authors’ Affiliations

Department of Mathematics, Community College of Philadelphia


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© Gao 2006

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