Analysis and Mathematical Physics

, Volume 9, Issue 3, pp 1227–1239 | Cite as

On differences of linear positive operators

  • Ali AralEmail author
  • Daniela Inoan
  • Ioan Raşa


In this paper we consider two different general linear positive operators defined on unbounded interval and obtain estimates for the differences of these operators in quantitative form. Our estimates involve an appropriate K-functional and a weighted modulus of smoothness. Similar estimates are obtained for Chebyshev functional of these operators as well. All considerations are based on rearrangement of the remainder in Taylor’s formula. The obtained results are applied for some well known linear positive operators.


K-functionals Weighted moduli of smoothness Chebyshev functional 

Mathematics Subject Classification

Primary 41A36 Secondary 41A25 


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of MathematicsKırıkkale UniversityYahşihanTurkey
  2. 2.Department of MathematicsTechnical University of Cluj-NapocaClujRomania

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