Superstability and Stability of the Pexiderized Multiplicative Functional Equation

Abstract

We obtain the superstability of the Pexiderized multiplicative functional equation f(xy)=g(x)h(y) and investigate the stability of this equation in the following form: 1/(1+ψ(x,y))≤f(xy)/g(x)h(y)≤1+ψ(x,y).