The Superstability of the Pexider Type Trigonometric Functional Equation
نویسندگان
چکیده
The aim of this paper is to investigate the stability problem for the Pexider type (hyperbolic) trigonometric functional equation f(x + y) + f(x + σy) = λg(x)h(y) under the conditions : |f(x + y) + f(x + σy)− λg(x)h(y)| ≤ φ(x), φ(y), and min{φ(x), φ(y)}. As a consequence, we have generalized the results of stability for the cosine(d’Alembert), sine, and the Wilson functional equations by J. Baker, P. Gǎvruta, R. Badora and R. Ger, Pl. Kannappan, and G. H. Kim.
منابع مشابه
On the Superstability of the Pexider Type Trigonometric Functional Equation
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