Generalized Hyers-Ulam Stability of General Cubic Functional Equation in Random Normed Spaces
Seong Sik Kim, John Michael Rassias, Nawab Hussain, Yeol Je Cho
In this paper, we investigate the generalized Hyers--Ulam stability of a general cubic functional equation:
$f(x+ky)-kf(x+y)+kf(x-y)-f(x-ky)=2k(k^2-1)f(y)$
for fixed $k\in\mathbb Z^+$ with $k\geq2$ in random normed spaces.