Applied Mathematics and Physics
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Applied Mathematics and Physics. 2017, 5(3), 95-98
DOI: 10.12691/amp-5-3-3
Open AccessArticle

Stability of Quadratic Functional Equationin Two Variables

Jianbing Cao1,

1Department of Mathematics, Henan Institute of Science and Technology, Xinxiang, China

Pub. Date: August 16, 2017

Cite this paper:
Jianbing Cao. Stability of Quadratic Functional Equationin Two Variables. Applied Mathematics and Physics. 2017; 5(3):95-98. doi: 10.12691/amp-5-3-3


In this paper, we establish the general solution of a 2-variable quadratic functional equation f(2x+y,2z+w)=f(x+y,z+w)-f(x-y,z-w)+4f(x,z)+f(y,w) and prove the generalized Hyers-Ulam stability of this functional equation.

solution stability quadratic functional equation

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