Title

APPROXIMATION BY EXPONENTIAL TYPE
VECTORS OF POSITIVE OPERATORS

Authors

Marian Dmytryshyn
Vasyl Stefanyk Precarpathian National University
57 Shevchenka str., 76018, Ivano-Frankivsk, UKRAINE

Abstract

We establish the estimations of best approximations of elements of a Banach space by exponential type vectors associated with the positive operator. The corresponding estimations are expressed in terms of quasi-norms of the approximation spaces as Bernstein-Jackson-type inequalities. Such inequalities are applied to spectral approximations in the case of the positive operator with the point spectrum.

History

Received: February 1, 2017
Revised: February 14, 2017
Published: February 19, 2017

AMS Classification, Key Words

AMS Subject Classification: 47A58, 41A17
Key Words and Phrases: exponential type entire vectors, Bernstein-Jackson-type inequalities, spectral approximations

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How to Cite?

DOI: 10.12732/ijpam.v112i4.10 How to cite this paper?

Source: International Journal of Pure and Applied Mathematics
ISSN printed version: 1311-8080
ISSN on-line version: 1314-3395
Year: 2017
Volume: 112
Issue: 4
Pages: 795 - 804

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This work is licensed under the Creative Commons Attribution International License (CC BY).

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