Which of the following sets are finite or infinite.

$\{1,2,3 \ldots .\}$

Match each of the set on the left described in the roster form with the same set on the right described in the set-builder form:

$(i)$  $\{ P,R,I,N,C,A,L\} $	$(a)$  $\{ x:x$ is a positive integer and is adivisor of $18\} $
$(ii)$  $\{ \,0\,\} $	$(b)$  $\{ x:x$ is an integer and ${x^2} - 9 = 0\} $
$(iii)$  $\{ 1,2,3,6,9,18\} $	$(c)$  $\{ x:x$ is an integer and $x + 1 = 1\} $
$(iv)$  $\{ 3, - 3\} $	$(d)$  $\{ x:x$ is aletter of the word $PRINCIPAL\} $

 

List all the elements of the following sers :

$B = \{ x:x$ is an integer $; - \frac{1}{2} < n < \frac{9}{2}\} $

Write the following sets in the set-builder form :

$\{ 2,4,6 \ldots \} $

State whether each of the following set is finite or infinite :

The set of circles passing through the origin $(0,0)$

Examine whether the following statements are true or false :

$\{ a,b\}  \not\subset \{ b,c,a\} $