True/false question Regarding closed subsets
73594
Existence of continuous function $f$ on $\Bbb R$ which vanishes exactly on $A\subset \Bbb R$
19289
complement of a set and its measure
158569
Proving a particular subset of $R^n$ is closed
70143
Mutually exclusive countable subsets of a countable set
146146
Proof that a closed subset of a compact space is a compact space
22854
Let $A , B\subseteq\mathbb{R}$. If $A$ is closed and $B$ is compact, is $A\cdot B$ closed?
46698
Showing a set is closed under inverses
44430
Is there an open dense set $S \subset [0,1]$ such that $m(S)<1$?
70959
Prove that a set $E$ is closed iff it's complement $E^{c}$ is open
58004
showing a collection of sets contain all closed sets
78117
Closed property of nonempty finite set
149820
How do you prove the set $G = \{(x, f(x)) \mid x \in \mathbb R\}$ is closed?
158155
Is set of isolated points of S closed?
36631
Is $[0,1] \cap \Bbb Q$ a compact subset of $\Bbb Q$?
147013
Subset of a finite set is finite
14219
Is the intersection of a closed set and a compact set always compact?
73130
A simple question about open set