elementary question about closed sets
68994
Countable closed sets
99236
Interior of closure of an open set
127173
Closed subset of compact set is compact
10180
How to prove that this set is closed?
148992
A finite set is closed
58004
showing a collection of sets contain all closed sets
34964
Recursive representation of closed sets in Baire Space ($\Sigma^1_1$)
144731
Disjoint closed sets in a second countable zero-dimensional space can be separated by a clopen set
36237
Closed set mapped to itself in a compact Hausdorff space
126897
Showing the set $A+B$ is closed.
73130
A simple question about open set
82333
let $(X,d)$ be a metric space. How I can show that any finite subset of $X$ is closed.
152927
seemingly nontrivial question about covering maps and evenly covered open sets
128482
The set of subsequential limits is closed
44623
Closed set as a countable intersection of open sets
36315
Is $[0,1]$ a countable disjoint union of closed sets?
128844
An empty intersection of decreasing sequence of closed sets