a. How can I prove that the intersection of two countable sets is countable?
hint: there is a very short answer
and
b. prove whether or not the intersection and union of two uncountable sets must be uncountable.
How do i even begin the second?
best answer will definitely be voted!
hint: there is a very short answer
and
b. prove whether or not the intersection and union of two uncountable sets must be uncountable.
How do i even begin the second?
best answer will definitely be voted!