Open Access

On the Generalized Favard-Kantorovich and Favard-Durrmeyer Operators in Exponential Function Spaces

Journal of Inequalities and Applications20082007:075142

DOI: 10.1155/2007/75142

Received: 18 January 2007

Accepted: 14 November 2007

Published: 9 January 2008


We consider the Kantorovich- and the Durrmeyer-type modifications of the generalized Favard operators and we prove an inverse approximation theorem for functions such that , where and , .


Authors’ Affiliations

Higher School of Marketing and Management
Faculty of Mathematics and Computer Science, Adam Mickiewicz University


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© G. Nowak and A. Sikorska-Nowak 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.