Union of connected sets also connected?
23225
Union of connected subsets is connected if intersection is nonempty
89506
Union of disjoint sets : Equivalence relations
156520
Intervals are connected and the only connected sets in $\mathbb{R}$
58285
Is it true that if $X$ is connected, then for every nonempty proper subset $A$ of $X$, we have $\mathbf{Bd} \ne \emptyset$
107564
If two sets have a natural (asymptotic) density, does their union?
147197
Number of connected components of the complement of a compact
147961
Characterizing simply connected spaces
39455
Prove that $(X\times Y)\setminus (A\times B)$ is connected
2575
Showing that $\mathbb{R}$ is connected
112050
Union of ascending chain of Topologies
31266
Proof of "the continuous image of a connected set is connected"
63442
Show that if $U$ is an open connected subspace of $\mathbb{R}^2$, then $U$ is path connected
146364
$X$ is connected iff $\forall A\subset X,$ $\partial A\neq\emptyset$
148399
Two sets which contain each other as elements
48557
Product of connected spaces
116866
$A\times B$ connected component implies $A,B$ connect components
77621
Continuity of function mapping connected set to connected set