Author:
Opraie Irina,Popa Dorian,Timboş Liana
Abstract
In this paper, we prove the Ulam stability of the Fréchet functional equation f(x+y+z)+f(x)+f(y)+f(z)=f(x+y)+f(y+z)+f(z+x) arising from the characterization of inner product spaces and we determine its best Ulam constant. Using this result, we give a stability result for a pexiderized version of the Fréchet functional equation.
Subject
General Mathematics,Engineering (miscellaneous),Computer Science (miscellaneous)
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