APPROXIMATE BI-HOMOMORPHISMS AND BI-DERIVATIONS IN C*-TERNARY ALGEBRAS

In this paper, we prove the generalized Hyers-Ulam stability of bi-homomorphisms in C*-ternary algebras and of bi-derivations on C*-ternary algebras for the following bi-additive functional equation f(x + y, z - w) + f(x - y, z + w) = 2f(x, z) - 2f(y, w). This is applied to investigate bi-isomorphisms between C*-ternary algebras.