Stability of the Quadratic Equation of Pexider Type
We will investigate the stability problem of the quadratic equation (1) and extend the results of Borelli and Forti, Czerwik, and Rassias. By applying this result and an improved theorem of the author, we will also prove the stability of the quadratic functional equation of Pexider type,f 1 (x +y) + f2(x -y) =f 3(x) +f 4(y), for a large class of functions.
Key words and phrasesQuadratic functional equation quadratic equation of Pexider type stability
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