Babe?-Bolyai University, Department of Mathematics, 1, M. Kog?lniceanu st., 400084 Cluj-Napoca, Romania
Abstract:
A new Korovkin-type theorem and its converse theorem are established. We compare our direct result with the Korovkin-type theorem given by Wang [15]. As applications we obtain quantitative estimates for q -Bernstein-type operators which preserve the functions e0(x)=1 and ej(x)=xj.