A FUNCTIONAL EQUATION RELATED TO QUADRATIC FORMS WITHOUT THE CROSS PRODUCT TERMS

• Journal title : Honam Mathematical Journal
• Volume 30, Issue 2,  2008, pp.219-225
• Publisher : The Honam Mathematical Society
• DOI : 10.5831/HMJ.2008.30.2.219
Title & Authors
A FUNCTIONAL EQUATION RELATED TO QUADRATIC FORMS WITHOUT THE CROSS PRODUCT TERMS
Park, Won-Gil; Bae, Jae-Hyeong;

Abstract
In this paper, we obtain the general solution and the stability of the 2-dimensional vector variable quadratic functional equation f( x + y, z - w) + f(x - y, z + w) = 2f(x, z ) + 2f(y, $\small{{\omega}}$). The quadratic form f( x, y) = $\small{ax^2}$ + $\small{by^2}$ without cross product terms is a solution of the above functional equation.
Keywords
Language
English
Cited by
1.
A Fixed Point Approach to the Stability of a Functional Equation,;;

Kyungpook mathematical journal, 2010. vol.50. 4, pp.557-564
1.
A Fixed Point Approach to the Stability of a Functional Equation, Kyungpook mathematical journal, 2010, 50, 4, 557
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