How do I prove that the set of all limit points of a set A is a closed set?
33310
Proving that the set of limit points of a set is closed
21820
How to prove that a set is invariant?
39293
Given a compact set $K$ and closed set $E,$ prove: $E\cap K\neq \emptyset $
143105
Show that, for every real number a, the set {$x ∈ S | f(x) ≤ a$} is a closed subset of $\mathbb R^d$
125962
The set $A'$ is closed in a $T_1$ space
106434
Prove that for a dense set $A$ and an open set $U$, $U\subset \overline{A\cap U}$
138607
Proof that a limit point compact metric space is compact.
130975
Given a pair of continuous functions from a topological space to an ordered set, how to prove that this set is closed?
97316
Let $F : X → X$ be continuous. Prove that the set $\{x ∈ X : F(x) = x\}$ of fixed points of F is closed in X
78117
Closed property of nonempty finite set
106957
Compact sets are closed?
16826
prove that every infinite subset of compact set H has a limit point (Explanation)
97373
Is whether a set is closed or not a local property?
94825
Open set as a finite union of closed sets
116009
Proving that if a set is both open and closed then it is equal to the real numbers
78300
Showing a set is closed other than giving a counterexample?
47056
Show that the boundary of a set equals the boundary of its complement