Sum of connected subsets is connected
104411
sum of two connected subset of $\mathbb{R}$
48557
Product of connected spaces
116538
Proof of Connected Diagrams
28683
Sum of two closed sets in $\mathbb R$ is closed?
26919
Intersection of Connected Sets
3392
Sum of products of elements of nonempty subsets of A set
123742
Proving connectedness of the $n$-sphere
39455
Prove that $(X\times Y)\setminus (A\times B)$ is connected
56370
Associative operation on a set $S$
84654
The graph of xy = 1 is connected or not
5132
Given $A\cap \overline{B}\neq \emptyset$, prove $A\cup B$ connected.
102323
Nice neighborhoods of each "piece" in a manifold connected sum
95373
Additive set function on a semiring of sets
93623
Showing that every connected open set in a locally path connected space is path connected
70538
Intersection and union of simply connected domain
127919
prove that if $E$ is connected and $E \subseteq F \subseteq \overline{E}$, then $F$ is connected.
30079
Is for open connected $U$ the set $U_\varepsilon$ for small $\varepsilon$ connected?