ON ω-CHEBYSHEV SUBSPACES IN BANACH SPACES

Abstract

The purpose of this paper is to introduce and discuss the concept of ${\omega}$-Chebyshev subspaces in Banach spaces. The concept of quasi Chebyshev in Banach space is defined. We show that ${\omega}$-Chebyshevity of subspaces are a new class in approximation theory. In this paper, also we consider orthogonality in normed spaces.

Keywords

• ${\omega}$-Chebyshev subspaces;
• orthogonality;
• proximinal subspaces;
• Chebyshev subspaces

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References

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Cited by

1. On simultaneous weakly-Chebyshev subspaces vol.27, pp.2, 2011, https://doi.org/10.1007/s10496-011-0117-4