ON SUPERCLASSES OF δ-OPEN SETS IN
Zanyar A. Ameen1, Baravan A. Asaad2, Ramadhan A. Muhammed3 1Department of Mathematics, College of Science
University of Duhok, IRAQ 2Department of Computer Science, College of Science
Cihan University-Duhok, IRAQ 2Department of Mathematics, Faculty of Science
University of Zakho, IRAQ 3Department of Mathematics, College of Basic Education
University of Duhok, IRAQ
The paper considers properties of -preopen, -semiopen, -open and -open sets in topological spaces. Particularly, we extend various results concerning these types of sets and give some more new results. Furthermore, we introduce two more subclasses of -semiopen sets, and study them.