Which of the following is the empty set
Which of the following sets are finite or infinite.
$\{1,2,3 \ldots .\}$
Let $A$ and $B$ be two non-empty subsets of a set $X$ such that $A$ is not a subset of $B$, then
Which of the following are sets ? Justify your answer.
The collection of all even integers.
The number of elements in the set $\{x \in R :(|x|-3)|x+4|=6\}$ is equal to