Write the following sets in roster form :
$\mathrm{E} =$ The set of all letters in the world $\mathrm{TRIGONOMETRY}$
$E =$ The set of all letters in the word $TRIGONOMETRY$
There are $12$ letters in the word $TRIGONOMETRY,$ out of which letters $T,$ $R$ and $O$ are repeated
Therefore, this set can be written in roster form as
$E =\{ T , R , I , G , O , N , M , E , Y \}$
The number of non-empty subsets of the set $\{1, 2, 3, 4\}$ is
Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:
$ 0\, ........\, A $
Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:
$ 5\, .......\, A$
State whether each of the following set is finite or infinite :
The set of lines which are parallel to the $x\,-$ axis
Which of the following pairs of sets are equal ? Justify your answer.
$A = \{ \,n:n \in Z$ and ${n^2}\, \le \,4\,\} $ and $B = \{ \,x:x \in R$ and ${x^2} - 3x + 2 = 0\,\} .$