Acta Mathematica Hungarica

, Volume 99, Issue 3, pp 203–208 | Cite as

Positive linear operators which preserve x2

  • J. P. King


A sequence of positive linear operators which approximate each continuous function on [0,1] while preserving the functione2(x) =x2 is presented. Quantitative estimates are given and are compared with estimates of approximation by Bernstein polynomials. Connections with summability are discussed.

Bernstein polynomials positive linear operators approximation summability 


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Copyright information

© Kluwer Academic Publishers/Akadémiai Kiadó 2003

Authors and Affiliations

  • J. P. King
    • 1
  1. 1.Department Of MathematicsLehigh UniversityBethlehem

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