Complex Operators Generated by q-Bernstein Polynomials, q≥1

Dedicated to the memory of Akif D. Gadjiev

Authors

  • Gülen BAȘCANBAZ-TUNCA Ankara University, Faculty of Science Department of Mathematics 06100, Tandogan, Ankara, Turkey e-mail: tunca@science.ankara.edu.tr https://orcid.org/0000-0003-3216-1661
  • Nursel ÇETIN Turkish State Meteorological Service Research Department 06120, Kecioren, Ankara, Turkey e-mail: nurselcetin07@gmail.com https://orcid.org/0000-0003-3771-6523
  • Sorin G. GAL Department of Mathematics and Computer Sciences University of Oradea Oradea, Romania e-mail: galso@uoradea.ro

Keywords:

q-Bernstein-type operator, Voronovskaja's theorem, quantitative estimates, complex rational operators, complex trigonometric polynomials.

Abstract

By using an univalent and analytic function τ in a suitable open disk centered in origin, we attach to analytic functions f, the complex Bernstein-type operators of the form B_{n,q}^{τ}(f)=B_{n,q}(f∘τ⁻¹)∘τ , where B_{n,q} denote the classical complex q-Bernstein polynomials, q≥1. The new complex operators satisfy the same quantitative estimates as B_{n,q}. As applications, for two concrete choices of τ, we construct complex rational functions and complex trigonometric polynomials which approximate f with a geometric rate.

Mathematics Subject Classification (2010): 30E10, 41A35, 41A25.

References

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Published

2016-06-30

How to Cite

BAȘCANBAZ-TUNCA, G., ÇETIN, N., & GAL, S. G. (2016). Complex Operators Generated by q-Bernstein Polynomials, q≥1: Dedicated to the memory of Akif D. Gadjiev. Studia Universitatis Babeș-Bolyai Mathematica, 61(2), 169–176. Retrieved from https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/5547

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