Let A be a set. Show that $\bigcup_{n\in\mathbb{N}}A^{n}$ is a set
100726
Prove that the set of powers of a set, $\{ A^n : n \in \mathbb{N} \}$ exists by using ZFC axioms (without replacement).
107383
Derived sets - prove $(A \cup B)' = A' \cup B'$
60707
Show that if $ \ A \cup B = A$ and $ \ A\cap B = A$ then $ \ A = B$
11817
Proving that every set $A \subset \Bbb N$ of size $n$ contains a subset $B \subset A$ with $n | \sum_{b \in B} b$
52787
If $\bigcup F = A$ then $A\in F$ then prove that $A$ has exactly one element
135814
Prove certain subsets of $\mathbb R^n$ are subspaces
17461
Show that a set is dense in $[-1,1]$
116527
Validating a proof for necessary and sufficient conditions on sets A & B such that $P(A) \cup P(B) = P(A\cup B)$
17510
Proving a set is an abelian group.
88982
Prove that for any two sets $A$ and $B$, $A\notin B$ or $B\notin A$
115606
Proofs involving $ (A\setminus B) \cup (A \cap B)$
75966
Prove that if $A$ is a set with $m$ elements, $B$ is a set with $n$ elements, and $A \cap B = \emptyset$, then $A \cup B$ has $m+n$ elements.
151719
Connected set in $\mathbb{S}^1$
57943
If $G$ is a convex set, prove that $\mathbb{C}\cup\{\infty\}\setminus G$ is connected.
154076
How to show this property of $\mathbb{RP}^{n}$.
123890
Show $A\setminus (A\cap B)=(A\cup B)\setminus B$
151852
How to prove $A \subset B \iff A \cup B = B$