A class of discretely defined positive linear operators satisfying DeVore-Gopengauz inequalities

Ioan Gavrea; Heinz H. Gonska; Daniela P. Kacso

Authors

Ioan Gavrea Technical University of Cluj-Napoca, Romania
Heinz H. Gonska University of Duisburg, Germany
Daniela P. Kacso University of Duisburg, Germany

Keywords:

positive linear operators, DeVore-Gopengauz inequalities, second order modulus of continuity, endpoint interpolation, simultaneous approximation

Abstract views: 221

Abstract

We construct a class of discretely defined positive linear operators satisfying DeVore-Gopengauz inequalities, i.e., pointwise estimates in terms of the classical second order modulus with endpoint interpolation. Thus we provide a solution to a stronger form of a problem of Butzer. Simultaneous approximation is addressed as well.

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References

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