Results 1 to 10 of about 4,449,819 (289)

Approximation on the Quadratic Reciprocal Functional Equation [PDF]

Journal of Function Spaces, 2014
The quadratic reciprocal functional equation is introduced. The Ulam stability problem for an ϵ-quadratic reciprocal mapping f:X→Y between nonzero real numbers is solved.
Abasalt Bodaghi, Sang Og Kim
doaj   +4 more sources

A Multidimensional Functional Equation Having Quadratic Forms as Solutions [PDF]

Journal of Inequalities and Applications, 2007
We obtain the general solution and the stability of the -variable quadratic functional equation The quadratic form is a solution of the given functional equation.
Bae Jae-Hyeong, Park Won-Gil
doaj   +5 more sources

Fuzzy Stability of a Quadratic-Additive Functional Equation [PDF]

International Journal of Mathematics and Mathematical Sciences, 2011
We investigate a fuzzy version of stability for the functional equation 𝑓(𝑥+𝑦+𝑧+𝑤)+2𝑓(𝑥)+2𝑓(𝑦)+2𝑓(𝑧)+2𝑓(𝑤)−𝑓(𝑥+𝑦)−𝑓(𝑥+𝑧)−𝑓(𝑥+𝑤)−𝑓(𝑦+𝑧)−𝑓(𝑦+𝑤)−𝑓(𝑧+𝑤)=0.
Sun Sook Jin, Yang Hi Lee
doaj   +3 more sources

The Stability of a Quadratic Functional Equation with the Fixed Point Alternative

Abstract and Applied Analysis, 2009
Lee, An and Park introduced the quadratic functional equation f(2x+y)+f(2x−y)=8f(x)+2f(y) and proved the stability of the quadratic functional equation in the spirit of Hyers, Ulam and Th. M. Rassias.
Choonkil Park, Ji-Hye Kim
doaj   +2 more sources

Fuzzy Stability of a General Quadratic Functional Equation [PDF]

Advances in Fuzzy Systems, 2011
We investigate a fuzzy version of stability for the functional equation 𝑓(𝑥+𝑦+𝑧)+𝑓(𝑥−𝑦)+𝑓(𝑥−𝑧)−𝑓(𝑥−𝑦−𝑧)−𝑓(𝑥+𝑦)−𝑓(𝑥+𝑧)=0 in the sense of M. Mirmostafaee and M. S. Moslehian.
Sun Sook Jin, Yang-Hi Lee
doaj   +4 more sources

Intuitionistic Fuzzy Stability of a Quadratic Functional Equation [PDF]

Fixed Point Theory and Applications, 2010
We consider the intuitionistic fuzzy stability of the quadratic functional equation by using the fixed point alternative, where is a positive integer.
Wang Liguang
doaj   +3 more sources

Stability Results of Quadratic-Additive Functional Equation Based on Hyers Technique in Matrix Paranormed Spaces

Mathematics, 2022
In this work, we introduce a mixed type of quadratic-additive (QA) functional equation and obtain its general solution. The objective of this work is to investigate the Ulam–Hyers stability of this quadratic-additive (QA) functional equation in matrix ...
Kandhasamy Tamilvanan, Yahya Almalki, Syed Abdul Mohiuddine, Ravi P. Agarwal   +3 more
doaj   +2 more sources

Quadratic functional equations of Pexider type

International Journal of Mathematics and Mathematical Sciences, 2000
First, the quadratic functional equation of Pexider type will be solved. By applying this result, we will also solve some functional equations of Pexider type which are closely associated with the quadratic equation.
Soon-Mo Jung
doaj   +2 more sources

Orthogonal Stability of an Additive-Quadratic Functional Equation [PDF]

Fixed Point Theory and Applications, 2011
Using the fixed point method and using the direct method, we prove the Hyers-Ulam stability of an orthogonally additive-quadratic functional equation in orthogonality spaces. (2010) Mathematics Subject Classification: Primary 39B55; 47H10; 39B52; 46H25.
Park Choonkil
doaj   +2 more sources

Characterization and stability analysis of advanced multi-quadratic functional equations

Advances in Difference Equations, 2021
In this paper, we introduce a new quadratic functional equation and, motivated by this equation, we investigate n-variables mappings which are quadratic in each variable.
Abasalt Bodaghi, Hossein Moshtagh, Hemen Dutta   +2 more
doaj   +1 more source