Which of the following are sets ? Justify your answer.
The collection of all the months of a year beginning with the letter $\mathrm{J}.$
The collection of all months of a year beginning with the letter $\mathrm{J}$ is a well-defined collection of objects because one can definitely identity a month that belongs to this collection.
Hence, this collection is a set.
Two finite sets have $m$ and $n$ elements. The total number of subsets of the first set is $56$ more than the total number of subsets of the second set. The values of $m$ and $n$ are
State which of the following sets are finite or infinite :
$\{ x:x \in N$ and $2x - 1 = 0\} $
Let $A, B$ and $C$ be three sets. If $A \in B$ and $B \subset C$, is it true that $A$ $\subset$ $C$ ?. If not, give an example.
List all the elements of the following sers :
$B = \{ x:x$ is an integer $; - \frac{1}{2} < n < \frac{9}{2}\} $