Results 1 to 10 of about 151,638 (261)
A system of biadditive functional equations in Banach algebras
Applied Mathematics in Science and Engineering, 2023 In this paper, we obtain the general solution and the Hyers-Ulam stability of the system of biadditive functional equations $$\begin{align*} \begin{cases} 2f(x+y,z+w)-g(x,z)-g(x,w)=g(y,z)+g(y,w)\\ g(x+y,z+w)-2f(x-y,z-w)=4f(x,w)+4f(y,z) \end{cases} \end ...
Yamin Sayyari +2 more
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A system of additive functional equations in complex Banach algebras
Demonstratio Mathematica, 2023 In this article, we solve the system of additive functional equations: 2f(x+y)−g(x)=g(y),g(x+y)−2f(y−x)=4f(x)\left\{\phantom{\rule[-1.25em]{}{0ex}}\begin{array}{l}2f\left(x+y)-g\left(x)=g(y),\\ g\left(x+y)-2f(y-x)=4f\left(x)\end{array}\right.
Paokanta Siriluk +3 more
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Combined system of additive functional equations in Banach algebras
Open MathematicsIn this study, we solve the system of additive functional equations: h(x+y)=h(x)+h(y),g(x+y)=f(x)+f(y),2fx+y2=g(x)+g(y),\left\{\begin{array}{l}h\left(x+y)=h\left(x)+h(y),\\ g\left(x+y)=f\left(x)+f(y),\\ 2f\left(\frac{x+y}{2}\right)=g\left(x)+g(y),\end ...
Donganont Siriluk, Park Choonkil
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Periodic solutions for an impulsive system of integro-differential equations with maxima [PDF]
Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2022 A periodical boundary value problem for a first-order system of ordinary integro-differential equations with impulsive effects and maxima is investigated.
Tursun K. Yuldashev
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Nonpotentiality of a diffusion system and the construction of a semi-bounded functional [PDF]
Қарағанды университетінің хабаршысы. Математика сериясы, 2021 The wide prevalence and the systematic variational principles are used in mathematics and applications due to a series of remarkable consequences among which the possibility to establish the existence of the solutions of the initial equations ...
V.M. Savchin, L.T. Huyen
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Attractors of 2D Navier–Stokes system of equations in a locally periodic porous medium [PDF]
Қарағанды университетінің хабаршысы. Математика сериясы, 2022 This article deals with two-dimensional Navier–Stokes system of equations with rapidly oscillating term in the equations and boundary conditions. Studying the problem in a perforated domain, the authors set homogeneous Dirichlet condition on the
K.A. Bekmaganbetov +2 more
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Solutions to a system of equations for $C^m$ functions [PDF]
Revista Matemática Iberoamericana, 2020 Fix m\geq 0 , and let A=(A_{ij}(x))_{1 \leq i \leq N, 1\leq j \leq M} be a matrix of semialgebraic functions on \mathbb{R}^
Fefferman, Charles, Luli, Garving K.
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ON A SYSTEM OF FUNCTIONAL EQUATIONS
Demonstratio Mathematica, 1998 The authors study the system of functional equations \[ \varphi_i(x)=\sum^n_{j=1}\sum^m_{k=1}a_{ijk}\biggl(x,\varphi_j\bigl(S_{ijk} (x)\bigr)\biggr)+g_i(x),\quad i=1,\dots,n,\quad x\in I\subset\mathbb{R}, \] where \(I\) is an interval and the given functions \(g_i:I\to I\) and \(a_{ijk}:I\times\mathbb{R}\to\mathbb{R}\) are continuous.
Nguyen Thanh Long +3 more
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Reduction of Linear Functional Systems using Fuhrmann's Equivalence
Sultan Qaboos University Journal for Science, 2016 Functional systems arise in the treatment of systems of partial differential equations, delay-differential equations, multidimensional equations, etc. The problem of reducing a linear functional system to a system containing fewer equations and unknowns ...
Mohamed S. Boudellioua
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Қарағанды университетінің хабаршысы. Математика сериясы, 2020 A semi-periodic initial boundary-value problem for a fourth-order system of partial differential equations is considered. Using the method of functional parametrization, an additional parameter is carried out and the studied problem is reduced to the ...
A.T. Assanova, Zh.S. Tokmurzin
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