Two cardinal inequalities for functionally Hausdorff spaces
نویسنده
چکیده
In this paper, two cardinal inequalities for functionally Hausdorff spaces are established. A bound on the cardinality of the τθ-closed hull of a subset of a functionally Hausdorff space is given. Moreover, the following theorem is proved: ifX is a functionally Hausdorff space, then |X| ≤ 2χ(X)wcd(X).
منابع مشابه
On the cardinality of functionally Hausdorff spaces
In this paper two new cardinal functions are introduced and investigated. In particular the following two theorems are proved: (i) If X is a functionally Hausdorff space then |X| ≤ 2fs(X)ψτ (X); (ii) Let X be a functionally Hausdorff space with fs(X) ≤ κ. Then there is a subset S of X such that |S| ≤ 2 and X = S {clτθ(A) : A ∈ [S] }.
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