... t)+|a|(q−3)nψq(y,s).(4.14)8 Journal of Inequalities and Applications4. Stability in (Rn) and Ᏺ(Rn)We are going to prove the stability theorem of the cubic functional equation in the spaces of (Rn)andᏲ(Rn).We ... stability of the linear functional equation, ” Proceedings of the NationalAcademy of Sciences of the United States of America, vol. 27, no. 4, pp. 222–224, 1941.[3] Th. M. Rassias, “On the stability ... Y. Chung 5 In this section, we consider the general solution of the cubic functional equation in the spaces of (Rn)andᏲ(Rn). It is well known that the semigroup property of the heatkernelEt∗...