An Example of a Stable Functional Equation When the Hyers Method Does Not Work
نویسندگان
چکیده
We show that the functional equation g ( x + y 2 ) = 4 √ g(x)g(y) is stable in the classical sense on arbitrary Q-algebraically open convex sets, but the Hyers method does not work. For the convenience of the reader, we have included an extensive list of references where stability theorems for functional equations were obtained using the direct method of Hyers.
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