Communications in Mathematics and Applications
Vol. 13, No. 3, pp. 1237–1247, 2022
ISSN 0975-8607 (online); 0976-5905 (print)
Published by RGN Publications http://www.rgnpublications.com
DOI: 10.26713/cma.v13i3.1619
Research Article
The Combination of Bernstein Polynomials
with Positive Functions Based on a Positive
Parameter s
Ali J. Mohammad and Rafah F. Katham*
Department of Mathematics, University of Basrah, Basrah, Iraq
*Corresponding author: rafah.fouad@gmail.com
Received: July 2, 2021 Accepted: August 9, 2022
Abstract. This paper deals with a sequence of the combination of Bernstein polynomials with a
positive function τ and based on a parameter s >−
1
2
. These polynomials have preserved the functions
1 and τ. First, the convergence theorem for this sequence is studied for a function f ∈ C[0, 1]. Next,
the rate of convergence theorem for these polynomials is descript by using the first, second modulus
of continuous and Ditzian-Totik modulus of smoothness. Also, the Quantitative Voronovskaja and
Grüss-Voronovskaja are obtained. Finally, two numerical examples are given for these polynomials by
chosen a test function f ∈ C[0, 1] and two functions for τ to show that the effect of the different values
of s and the different chosen functions τ.
Keywords. Bernstein polynomials, Modulus of smoothness, Quantitative Voronovskaja, Grüss-
Voronovskaja
Mathematics Subject Classification (2020). 41A10, 41A25, 41A36
Copyright © 2022 Ali J. Mohammad and Rafah F. Katham. This is an open access article distributed under the
Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any
medium, provided the original work is properly cited.
1. Introduction
For a function f ∈ C[0, 1], the well-known Bernstein polynomials [1] are defined as:
B
n
( f ; x) =
n
X
k=0
b
n,k
( x) f
k
n
¶
(1.1)
where b
n
( x) =
(
n
k
)
x
k
(1 − x)
n−k
and x ∈ [0, 1].