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On approximation by some Bernstein–Kantorovich exponential-type polynomials

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Abstract

Since the introduction of Bernstein operators, many authors defined and/or studied Bernstein type operators and their generalizations, among them are Morigi and Neamtu (Adv Comput Math 12:133–149, 2000). They proposed an analog of classical Bernstein operator and proved some convergence results for continuous functions. Herein, we introduce their integral extensions in Kantorovich sense by replacing the usual differential and integral operators with their more general analogues. By means of these operators, we are able to reconstruct the functions which are not necessarily continuous. It is shown that the operators form an approximation process in both \(C\left[ 0,1\right] \) and \(L_{p,\mu }\left[ 0,1\right] \), which is an exponentially weighted space. Also, quantitative results are stated in terms of appropriate moduli of smoothness and K-functionals. Furthermore, a quantitative Voronovskaya type result is presented.

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Acknowledgements

We are grateful to the referee for very helpful comments and suggestions.

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Authors and Affiliations

  1. Department of Mathematics, Faculty of Sciences and Arts, Kırıkkale University, 71450, Kırıkkale, Turkey

    Ali Aral

  2. Department of Mathematics, Faculty of Automation and Computer Science, Technical University of Cluj-Napoca, Memorandumului St. no. 28, 400114, Cluj-Napoca, Romania

    Diana Otrocol & Ioan Raşa

  3. Tiberiu Popoviciu Institute of Numerical Analysis, Romanian Academy, P.O. Box. 68-1, 400110, Cluj-Napoca, Romania

    Diana Otrocol

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  1. Ali Aral
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  2. Diana Otrocol
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Correspondence to Ali Aral.

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Aral, A., Otrocol, D. & Raşa, I. On approximation by some Bernstein–Kantorovich exponential-type polynomials. Period Math Hung 79, 236–254 (2019). https://doi.org/10.1007/s10998-019-00284-3

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