Characterizations of Strongly Compact Spaces

A topological space X, τ is said to be strongly compact if every preopen cover of X, τ admits a finite subcover. In this paper, we introduce a new class of sets called N-preopen sets which is weaker than both open sets and N-open sets. Where a subset A is said to be N-preopen if for each x ∈ A there exists a preopen set Ux containing x such that Ux − A is a finite set. We investigate some properties of the sets. Moreover, we obtain new characterizations and preserving theorems of strongly compact spaces.