International Journal of Mathematics and Mathematical Sciences
Volume 20 (1997), Issue 2, Pages 263-266
doi:10.1155/S0161171297000355

On a conjecture of Vukman

Qing Deng

Department of Mathematics, Southwest China Normal University, Chongqing 630715, China

Abstract

Let R be a ring A bi-additive symmetric mapping d:R×RR is called a symmetric bi-derivation if, for any fixed yR, the mapping xD(x,y) is a derivation. The purpose of this paper is to prove the following conjecture of Vukman.Let R be a noncommutative prime ring with suitable characteristic restrictions, and let D:R×RR and f:xD(x,x) be a symmetric bi-derivation and its trace, respectively. Suppose that fn(x)Z(R) for all xR, where fk+1(x)=[fk(x),x] for k1 and f1(x)=f(x), then D=0.