GENERALIZED (Ơ,t) – (U,R) – DERIVATIONS

Let R be a ring not necessarily with an identity element. Let U be a lie ideal in R. In this paper we define a (s,t) – (U,R) – derivation and we prove that if R is a prime ring of char¹ 2 and U is a square closed lie ideal of R and d is (s,t) – (U,R) – derivation then d(ur) = d(u) s(r) + t(u) d(r) for all u€U, r€R. also we introduce the generalized (s,t) – (U,R) – derivation then we generalized the previous result to the generalized (s,t) – (U,R) – derivation.