Results 21 to 30 of about 164,099 (264)

On extension of solutions of a simultaneous system of iterative functional equations [PDF]

open access: yesOpuscula Mathematica, 2009
Some sufficient conditions which allow to extend every local solution of a simultaneous system of equations in a single variable of the form \[ \varphi(x) = h (x, \varphi[f_1(x)],\ldots,\varphi[f_m(x)]),\] \[\varphi(x) = H (x, \varphi[F_1(x)],\ldots ...
Janusz Matkowski
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Method of functional parametrization for solving a semi-periodic initial problem for fourth-order partial differential equations

open access: yesҚарағанды 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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Existence and uniqueness of solutions for certain functional equations and system of functional equations arising in dynamic programming

open access: yesAnalele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2016
This paper deals with the existence, uniqueness and iterative approximations of solutions for the functional equations and system of functional equations arising in dynamic programming of multistage decision making processes in Banach spaces and complete
Deepmala, Agarwal Ravi P.
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Representation and perturbations of a system of additive-quadratic functional equations [PDF]

open access: yesMathematics and Computational Sciences
In the present article, we introduce a novel multimixed additive-quadratic mapping, and then show that the system of several mixed additive-quadratic equations defining a multimixed additive-quadratic mapping can be described as one single equation.
Abasalt Bodaghi
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Stability results for the functional differential equations associated to water hammer in hydraulics

open access: yesElectronic Journal of Qualitative Theory of Differential Equations, 2022
There is considered a system of two sets of partial differential equations describing the water hammer in a hydroelectric power plant containing the dynamics of the tunnel, turbine penstock, surge tank and hydraulic turbine.
Vladimir Rasvan
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CANONICAL APPROXIMATIONS IN IMPULSE STABILIZATION FOR A SYSTEM WITH AFTEREFFECT

open access: yesUral Mathematical Journal, 2023
For optimal stabilization of an autonomous linear system of differential equations with aftereffect and impulse controls, the formulation of the problem in the functional state space is used.
Yuri F. Dolgii
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On systems of linear functional equations

open access: yesAequationes Mathematicae, 1982
The square functional equation \[ (1)\quad f(x+t,y+t)+f(x+t,y-t)+f(x-t,y- t)+f(x-t,y+t)=4f(x,y), \] where f: \(R\times R\to R\) and x, y, t are real variables, was investigated by \textit{J. Acźel}, the reviewer, \textit{M. A. McKiernan} and \textit{G.N. Sakovič} [ibid. 1, 37-53 (1968; Zbl 0157.461)].
Laird, P.G., Mills, J.
openaire   +4 more sources

Functional Equations and Poincaré Invariant Mechanical Systems

open access: yesSIAM Journal on Mathematical Analysis, 2002
We study the following functional equation that has arisen in the context of mechanical systems invariant under the Poincare algebra: \sum\limits_{i=1}^{n+1}\dfrac{\partial}{\partial x_{i}}\prod\limits_{j\neq i}f(x_{i}-x_{j}) =0,\qquad n \geq 2. New techniques are developed and the general solution within a certain class of functions is given.
John G. B. Byatt-Smith, Harry W. Braden
openaire   +4 more sources

On the correctness of the determination of trigonometric functions by the system of functional equations

open access: yesKarpatsʹkì Matematičnì Publìkacìï, 2013
The article shows that the system of the functional equations $S(x+y)=S(x)C(y)+S(y)C(x),\,C(x+y)=C(x)C(y)-S(y)S(x)$ denes a broader class of the functions than the trigonometric equations.
Е. V. Velichko, I. G. Tkachenko
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Weak Solutions of a Coupled System of Urysohn-Stieltjes Functional (Delayed) Integral Equations

open access: yesComplexity, 2018
We study the existence of weak solutions for the coupled system of functional integral equations of Urysohn-Stieltjes type in the reflexive Banach space E.
A. M. A. El-Sayed, M. M. A. Al-Fadel
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