Write the following sets in the set-builder form :
$\{ 2,4,6 \ldots \} $
In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.
If $A \subset B$ and $x \notin B,$ then $x \notin A$
State which of the following sets are finite or infinite :
$\{ x:x \in N$ and $2x - 1 = 0\} $
State whether each of the following set is finite or infinite :
The set of numbers which are multiple of $5$
If a set $A$ has $n$ elements, then the total number of subsets of $A$ is