What is closure $\Bbb Q \cap [0,1]$?
10477
Finding the closure of A=$\mathbb Q \cap [0,1]$.
128381
Branches of $\log(z)$ on $\mathbb{C}\backslash(-\infty,0]$?
75863
how to prove $f^{-1}(B_1 \cap B_2) = f^{-1}(B_1) \cap f^{-1}(B_2)$
142093
The closure of an irreducible subset of an irreducible space is irreducible.
31124
The closure of $c_{00}$ is $c_{0}$ in $\ell^\infty$
52135
Show that $A \setminus ( B \setminus C ) \equiv ( A \setminus B) \cup ( A \cap C )$
7903
Prove that $B[x] \cap B[x^{-1}]$ is integral over $B$
39293
Given a compact set $K$ and closed set $E,$ prove: $E\cap K\neq \emptyset $
137711
Alternative proof that $[\Bbb{Q}(\zeta_n) : \Bbb{Q} ]= \varphi(n)$ uses circular reasoning?
64871
Closure of Union contains Union of Closures
51687
Is the set $ \ (\mathbb{Z}_p \setminus \mathbb{Z}) \cap \mathbb{Q}$ non-empty?
108156
Algebraic closure of $\mathbb{C}(x)$ is isomorphic to $\mathbb{C}$
21176
Closure of the set in dictionary order topology.
107370
An open covering of $\mathbb{Q} \cap [0,1]$ that does not contain any finite subcovering
139499
The algebraic closure of a finite field and its Galois group
113175
Why is the algebraic closure of a finite field countable?
67637
How come $\lambda(\mathbb{Q})= \inf\left\{\sum_{n \ge 1} \lambda([a_n,b_n)) : \mathbb{Q} \subset \bigcup_{n \ge 1} [a_n,b_n)\right\} = 0$?