State which of the following sets are finite or infinite :

$\{ x:x \in N$ and $2x – 1 = 0\} $

State which of the following sets are finite or infinite :

$\{ x:x \in N$ and ${x^2} = 4\} $

Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:

$ 8\, …….\, A $

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 ${x^2} – 3x + 2 = 0\,\} .$

Write down all the subsets of the following sets

$\{ a\} $