ON ω-CHEBYSHEV SUBSPACES IN BANACH SPACES

Title & Authors
ON ω-CHEBYSHEV SUBSPACES IN BANACH SPACES
Shams, Maram; Mazaheri, Hamid; Vaezpour, Sayed Mansour;

Abstract
The purpose of this paper is to introduce and discuss the concept of $\small{{\omega}}$-Chebyshev subspaces in Banach spaces. The concept of quasi Chebyshev in Banach space is defined. We show that $\small{{\omega}}$-Chebyshevity of subspaces are a new class in approximation theory. In this paper, also we consider orthogonality in normed spaces.
Keywords
$\small{{\omega}}$-Chebyshev subspaces;orthogonality;proximinal subspaces;Chebyshev subspaces;
Language
English
Cited by
1.
On simultaneous weakly-Chebyshev subspaces, Analysis in Theory and Applications, 2011, 27, 2, 117
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