Asılbek ÇEKEEV

Proceedings Paper | 2019 | Filomat33 ( 5 )

A number of basic properties of R-compact spaces in the category Tych of Tychonoff spaces and their continuous mappings are extended to the category ZUnif of uniform spaces with the special normal bases and their coz-mappings.

Fahreddin ABDULLAYEV

Article | 2017 | Filomat31 ( 18 )

In this work, we investigate the order of the growth of the modulus of orthogonal polynomials over a contour and also arbitrary algebraic polynomials in regions with corners in a weighted Lebesgue space, where the singularities of contour and the weight functions satisfy some condition.

Dağıstan ŞİMŞEK | Burak OĞUL

Proceedings Paper | 2019 | Filomat33 ( 5 )

In this paper, solution of the following difference equation is examined x(n+1) = x(n-17)/1+x(n-5).x(n-11) where the initial conditions are positive reel numbers.

Fahreddin ABDULLAYEV

Proceedings Paper | 2019 | Filomat33 ( 5 )

In the paper, exact constants in direct and inverse approximation theorems for functions of several variables are found in the spaces S-p. The equivalence between moduli of smoothness and some K-functionals is also shown in the spaces S-p.

Fahreddin ABDULLAYEV

Proceedings Paper | 2019 | Filomat33 ( 5 )

We describe the set of holomorphic functions from the Hardy space H-q, 1

Avıt ASANOV

Proceedings Paper | 2019 | Filomat33 ( 5 )

In this work, we apply the method of integral transformation to prove uniqueness theorems for the new class of Fredholm linear integral equations of the first kind in the axis.

Asılbek ÇEKEEV

Article | 2018 | Filomat32 ( 14 )

In this paper, it is established a characterization of T-normal coverings by means of approximation of the Cech complete paracompacta, which are the perfect preimages of complete metric spaces of weight

Asan ÖMÜRALİEV | Ella ABILAYEVA

Article | 2022 | Filomat36 ( 16 )

The regularization method for singularly perturbed problems of S. A. Lomov is generalized to constructing the asymptotics of the solution of the first boundary value problem for systems of differential equations of parabolic type with a small parameter at all derivatives.It is shown that the asymptotics of the solution of the problem contains n exponential, 2n parabolic and 2n angle boundary layer functions.The exponential boundary layer function describes the boundary layer along t 0, the boundary layer along x 0 and x 1 is described by parabolic boundary layer functions. © 2022, University of Nis. All rights reserved.Keyword: para . . .bolic boundary layer function; regularized asymptotic; singularly perturbed; the system of parabolic equation More less

Meerim İmaş Kızı | Fahreddin ABDULLAYEV

Article | 2023 | Filomat37 ( 17 )

In this paper, we study Bernstein, Markov and Nikol’skii type inequalities for arbitrary algebraic polynomials with respect to a weighted Lebesgue space, where the contour and weight functions have some singularities on a given contour. Keyword: In this paper, we study Bernstein, Markov and Nikol’skii type inequalities for arbitrary algebraic polynomials with respect to a weighted Lebesgue space, where the contour and weight functions have some singularities on a given contour

Anarkül URDALETOVA

Proceedings Paper | 2019 | Filomat33 ( 5 )

Traditionally the Euler method is used for solving systems of linear differential equations. The method is based on the use of eigenvalues of a system's coefficients matrix. Another method to solve those systems is the D'Alembert integrable combination method. In this paper, we present a new method for solving systems of linear differential and difference equations. The main idea of the method is using the coefficients matrix eigenvalues to find integrable combinations of system variables. This method is particularly advantageous when nonhomogeneous systems are considered.

Asan ÖMÜRALİEV | Peyil Esengul Kızı

Proceedings Paper | 2019 | Filomat33 ( 5 )

The Cauchy problem with a rapidly oscillating initial condition for the homogeneous Schrodinger equation was studied in [5]. Continuing the research ideas of this work and [3], in this paper we construct the asymptotic solution to the following mixed problem for the nonstationary Schrodinger equation: L(h)u ih partial derivative(t)u + h(2)partial derivative(2)(x)u - b(x,t)u = f(x,t) (x,t) is an element of Omega = (0,1) x (0,t], u vertical bar(t=0) = g(x), u vertical bar(x=0) = u vertical bar(x=1) = 0 where h > 0 is a Planck constant, u = u(x,t,h). b(x,t), f (x,t) is an element of C-infinity(Omega),g (x) is an element of C-infinit . . .y[0,1] are given functions. The similar problem was studied in [7, 8] when the Plank constant is absent in the first term of the equation and asymptotics of solution of any order with respect to a parameter was constructed. In this paper, we use a generalization of the method used in [7] More less

Fahreddin ABDULLAYEV

Proceedings Paper | 2019 | Filomat33 ( 2 )

In this study, we give some estimates on the Nikolskii-type inequalities for complex algebraic polynomials in regions with piecewise smooth curves having exterior and interior zero angles.