FRACTIONAL TRIGONOMETRIC KOROVKIN THEORY

TitleFRACTIONAL TRIGONOMETRIC KOROVKIN THEORY
Publication TypeJournal Article
Year of Publication2010
AuthorsAnastassiou, GA
Secondary TitleCommunications in Applied Analysis
Volume14
Issue1
Start Page39
Pagination58
Date Published01/2006
Type of Workscientific: mathematics
ISSN1083–2564
AMS26A33, 41A17, 41A25, 41A36, 41A80.
Abstract
In this article we study quantitatively with rates the trigonometric weak convergence of a sequence of finite positive measures to the unit measure. Equivalently we study quantitatively the trigonometric pointwise convergence of sequence of positive linear operators to the unit operator, all acting on continuous functions on [−π, π]. From there we derive with rates the corresponding trigonometric uniform convergence of the last. Our inequalities for all of the above in their right hand sides contain the moduli of continuity of the right and left Caputo fractional derivatives of the involved function. From our uniform trigonometric Shisha-Mond type inequality we derive the first trigonometric fractional Korovkin type theorem regarding the trigonometric uniform convergence of positive linear operators to the unit. We give applications, especially to Bernstein polynomials over [−π, π] for which we establish fractional trigonometric quantitative results.
URLhttp://www.acadsol.eu/en/articles/14/1/4.pdf
Short TitleFRACTIONAL TRIGONOMETRIC KOROVKIN THEORY
Refereed DesignationRefereed
Full Text
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