Characterizations of rotundity and smoothness by approximate orthogonalities
Abstract
In this paper we consider the approximate orthogonalities in real normed spaces. Using the notion of approximate orthogonalities in real normed spaces, we provide some new characterizations of rotundity and smoothness of dual spaces.
Keywords
approximate orthogonality; rotundity; smoothness; dual space; norm derivatives
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Instytut Matematyki, Uniwersytet Pedagogiczny im. Komisji Edukacji Narodowej w Krakowie Poland
Instytut Matematyki, Uniwersytet Pedagogiczny im. Komisji Edukacji Narodowej w Krakowie Poland
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