An equivalent condition to normality of topological spaces
102924
Normal space- equivalent condition: $\forall U, V$ - open $: U \cup V = X \ \ \ \exists F \subset U \ , G \subset V$ - closed $: F \cup G = X$
130975
Given a pair of continuous functions from a topological space to an ordered set, how to prove that this set is closed?
120311
Equivalence of Axiom of Regularity
25997
Conditions Equivalent to Injectivity
52388
The equivalence of open-set definition of continuous mappings to the $\epsilon-\delta$ definition
108864
Showing that two topologies give rise to the same topology
70049
Irreducible topological spaces and irreducible Hausdorff space
128266
Dual Spaces and Natural maps
4064
An equality involving the mean value property
111360
Topological spaces in which every proper closed subset is compact
125244
Equivalent definitions of normal subgroups
155621
Finiteness of the dimension of a normed space and compactness
154762
Dual space of a finite dimensional normed space
120252
Equivalences of bounded sets definitions
135025
Axiomatization of a Topology using the Boundary
120345
Topology induced by seminorms and initial topology
4834
Proving that unconditional convergence is equivalent to absolute convergence