Hostname: page-component-77c89778f8-vsgnj Total loading time: 0 Render date: 2024-07-20T12:39:13.793Z Has data issue: false hasContentIssue false

Sharp estimates of approximation by some positive linear operators

Published online by Cambridge University Press:  17 April 2009

Ashok Sahai
Affiliation:
Department of Mathematics, University of Roorkee, Roorkee, U.P. 247667, India.
Govind Prasad
Affiliation:
Department of Mathematics, University of Roorkee, Roorkee, U.P. 247667, India.
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Recently, Varshney and Singh [Rend. Mat. (6) 2 (1982), 219–225] have given sharper quantitative estimates of convergence for Bernstein polynomials, Szasz and Meyer-Konig-Zeller operators. We have achieved improvement over these estimates by taking moments of higher order. For example, in case of the Meyer-Konig-Zeller operator, they gave the following estimate

wherein ∥·∥ stands for sup norm. We have improved this result to

We may remark here that for this modulus of continuity ) our result cannot be sharpened further by taking higher order moments.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1984

References

[1]Rathore, R.K.S., “Lipschitz-Nikolski constants and asymptotic simultaneous approximation of the M n-operators”, Aequationes Math. 18 (1978), 206217.CrossRefGoogle Scholar
[2]Varshney, Om P. and Singh, S.P., “On degree of approximation by positive linear operators”, Rend. Mat. (7) 2 (1982), 219225.Google Scholar