Journal of Inequalities and Applications
Volume 2010 (2010), Article ID 323609, 17 pages
Research Article

On Sharp Triangle Inequalities in Banach Spaces II

1Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Niigata Institute of Technology, Kashiwazaki 945-1195, Japan
2Department of Mathematics, Faculty of Science, Niigata University, Niigata 950-2181, Japan

Received 4 November 2009; Accepted 2 March 2010

Academic Editor: Vy Khoi Le

Copyright © 2010 Ken-Ichi Mitani and Kichi-Suke Saito. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Sharp triangle inequality and its reverse in Banach spaces were recently showed by Mitani et al. (2007). In this paper, we present equality attainedness for these inequalities in strictly convex Banach spaces.