On the stability of quadratic functional equations in \(F\)-spaces
Summary: The Hyers-Ulam-Rassias stability of quadratic functional equation \(f(2 x + y) + f(2 x - y) = f(x + y) + f(x - y) + 6 f(x)\) and orthogonal stability of the Pexiderized quadratic functional equation \(f(x + y) + f(x - y) = 2 g(x) + 2 h(y)\) in \(F\)-spaces are proved.
pexiderized quadratic functional equation
scientific article; zbMATH DE number 6614009
scientific article