Prove that an uncountable set X is equivalent to X\Y where Y is a denumerable subset of X
48523
Let $A$ be any uncountable set, and let $B$ be a countable subset of $A$. Prove that the cardinality of $A = A - B $
63276
Is an arbitrary union of a chain of countable sets countable?
33157
Proof that an infinite subset of $\mathbb{N}$ is countable
130981
Co-countable measure on uncountable set
123613
Double Complement of a set proof
122463
How to show the that a set $A$ nowhere dense is equivalent to the complement of $A$ containing a dense open set?
83518
Proving Two sets have same cardinality
67064
Uncountable minus countable set is uncountable
75019
Infinite Cartesian product of countable sets is uncountable
91163
Let the set S be infinite, and the set T countably infinite. Show that S and S U T have the same cardinality
151295
Proving $|S \times \mathbb{N}|=|S|$ when $S$ is an infinite set
66548
proving topological equivalence
89167
Cardinality of equivalence relations in $\mathbb{N}$
128437
How to prove that a finite set is countable
23442
Cardinality of the union of infinite and countable sets
28539
Does any uncountable set contain two disjoint uncountable sets?
103769
The Cartesian product of a finite number of countable sets is countable