Bihom derivations in Banach algebras

Abstract

In this paper, we introduce bihom derivations in complex Banach algebras. Using the fixed point method and the direct method, we prove the Hyers–Ulam stability of bihom derivations in complex Banach algebras, associated with the bi-additive s-functional inequality $$\Vert f(x+y, z-w) + f(x-y, z+w) -2f(x,z)+2 f(y, w)\Vert \le \Vert s \left( 2f\left( \frac{x+y}{2}, z-w\right) + 2f\left( \frac{x-y}{2}, z+w\right) - 2f(x,z )+ 2 f(y, w)\right) \Vert $$ , where s is a fixed nonzero complex number with $$|s |< 1$$ .