Cite this article as:

Shakh-Emirov T. N. On Convergence of Bernstein – Kantorovich Operators sequence in Variable Exponent Lebesgue Spaces. Izv. Saratov Univ. (N. S.), Ser. Math. Mech. Inform., 2016, vol. 16, iss. 3, pp. 322-330. DOI: https://doi.org/10.18500/1816-9791-2016-16-3-322-330


Published online: 
03.10.2016
Language: 
Russian
Heading: 
UDC: 
517.51

On Convergence of Bernstein – Kantorovich Operators sequence in Variable Exponent Lebesgue Spaces

Abstract: 

Let E = [0, 1] and let a function p(x) > 1 be measurable and essentially bounded on E. We denote by L p(x) (E) the set of measurable function f on E for which R E |f(x)| p(x) dx < ∞. The convergence of a sequence of operators of Bernstein – Kantorovich {Kn(f, x)} ∞n=1 to the function f in Lebesgue spaces with variable exponent L p(x) (E) is studied. The conditions on the variable exponent at which this sequence is uniformly bounded in these spaces are obtained and, as a corollary, it is shown that if n → ∞ then Kn(f, x) converges to function f in the metric of space L p(x) (E) defined by the norm.

References

1. Kantorovich L. V. Sur certains developpements suivant les polynoˆmes de la forme de S. Bernstein I, II. C. R. Acad. Sci. URSS, 1930, pp. 563– 568; pp. 595–600.

2. Lorentz G. G. Bernstein Polynomials. Toronto, Univ. Toronto Press, 1953, 130 p.

3. Sharapudinov I. I. Topology of the space L p(t) ([0, 1]). Math. Notes, 1979, vol. 26, iss 4, pp. 796–806. DOI: https://doi.org/10.1007/BF01159546.

4. Sharapudinov I. I. Nekotorye voprosy teorii priblizhenii v prostranstvakh Lebega s peremennym pokazatelem [Some aspects of approximation theory in variable Lebesgue spaces]. YuMI VNTs RAN i RSO-A, Vladikavkaz, 2012, 270 p. (in Russian).

5. Natanson I. P. Konstruktivnaia teoriia funktsii [Constructive theory of functions]. Moscow ; Leningrad, GITTL, 1949. 688 p. (in Russian).

6. Borovkov A. A. Teoriia veroiatnostei : ucheb. posobie dlia vuzov [Probability Theory : Textbook for High Schools]. Moscow, Nauka, 1986, 432 p. (in Russian).

7. Vulih B. Z. Vvedenie v funktsional’nyi analiz [Introduction to functional analisys]. Moscow, Nauka, 1967, 416 p. (in Russian).

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