Quantitative results for positive linear operators which preserve certain functions

  • 1 Technical University of Cluj Napoca, Cluj Napoca


In this paper we obtain estimations of the errors in approximation by positive linear operators which fix certain functions. We use both the first and the second order classical moduli of smoothness and a generalized modulus of continuity of order two. Some applications involving Bernstein type operators, Kantorovich type operators and genuine Bernstein-Durrmeyer type operators are presented.

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