Projection of closed set
115272
Showing that projections $\mathbb{R}^2 \to \mathbb{R}$ are not closed
97761
Show that a proper continuous map from $X$ to locally compact $Y$ is closed
55614
Prove that a set consisting of a sequence and its limit point is closed
148992
A finite set is closed
99236
Interior of closure of an open set
17159
Proof of Closest Point Theorem in Hilbert Space
156101
Is the convex hull of closed set in $\mathbb R^{n}$ is closed?
8414
Proof verification: Set of partial limits of a sequence is closed
158569
Proving a particular subset of $R^n$ is closed
58101
The set of points where two maps agree is closed?
40438
Proving that closed (and open) balls are convex
92774
Prove that a linear subspace of $C([0,1])$ is closed
156922
Proving convergence iff projection converges in product topology
42698
Set of limit points of a subset of a Hausdorff space is closed.
93165
A projection satisfying $\| Px \| \leq \|x\|$ for all $x$ is an orthogonal projection
22558
Vitali-type set with given outer measure
126897
Showing the set $A+B$ is closed.