Document Type: Special Issue on Fixed Point Theory


1 Department of Mathematics, Semnan University, P.O. Box 35195-363, Semnan, Iran

2 Department of Mathematics, Payame Noor University, P.O. BOX 19395-4697, Tehran, Iran


In this paper, we first present the new concept of $2$-normed algebra. We investigate the structure of this algebra and give some examples. Then we apply a fixed point theorem to prove the stability and hyperstability of $(\alpha, \beta, \gamma)$-derivations in $2$-Banach algebras.


Main Subjects

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