Closure of closure of set equals closure of set
63717
Is the closure of a set equal to the closure of the closure of that set?
8015
Compact set plus a closed set is a closed set
73338
Prove that the closure of complement, is the complement of the interior
157603
Continuity $\iff$ Preimage is closed whenever set is closed
18462
Transitivity check vs. Transitive Closure
107281
Proof of Existence of Algebraic Closure: Too simple to be true?
89506
Union of disjoint sets : Equivalence relations
44623
Closed set as a countable intersection of open sets
54497
Set Notation - Inclusion and Proper Inclusion
97373
Is whether a set is closed or not a local property?
142459
Continuity of a Function in Terms of Closure and Interior
48797
Proving Two Sets are Equal - Infinite Sets - Example
42494
The boundary is a closed set
143457
Is product of two closed sets closed?
130975
Given a pair of continuous functions from a topological space to an ordered set, how to prove that this set is closed?
86317
Show that $F\subset Y$ is closed in $Y$ iff $F=Y\;\cap\;H$ where $H\subset X$ is closed in $X$.
10180
How to prove that this set is closed?