Abstract
The extremal elements of the unit balls of Banach spaces play an important role in the study of the geometry of the space as well in various applications. For Banach spaces of Lipschitz real functions the extremal elements of the unit ball are investigates in numerous papers (S. Cobzas 1989, J. D. Farmer 1994, N. V. Rao and A. C. Roy 1970, Roy 1968 and in the references therein). In this note we shall present a procedure to obtain extremal elements of the unit ball of the quasi normed semilinear space of real-valued semi-Lipschitz functions defined on a quasi-metric space.
Authors
Costica Mustata
“Tiberiu Popoviciu” Institute of Numerical Analysis, Romanian Academy, Romania
Keywords
semi metric spaces; semi Lipschitz real functions.
Paper coordinates
C. Mustăţa, On the extremal semi-Lipschitz function, Rev. Anal. Numer. Theor. Approx. 31 (2002) no. 1, 103-108.
About this paper
Journal
Revue d’Analyse Numer.Theor. Approx.
Publisher Name
Publishing Romanian Academy
Print ISSN
2457-6794
Online ISSN
2501-059X
google scholar link
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