Match each of the sets on the left described in the roster from with the same
set on the right described in the set-builder from:
(i) {-5, 5}
It can be seen that if we take the square of -5 and 5, the result will be 25
If $x=-5$, then $(-5)^{2}=25$
If $x=5$, then $(5)^{2}=25$
and -5, 5 both are integers
So, $\left\{x: x \in Z\right.$ and $\left.x^{2}=25\right\}$
$\therefore$ (i) matches (c)
(ii) $\{1,2,3,6,9,18\}$
Divisor of 18 are
$18=18 \times 1$
$18=9 \times 2$
$18=6 \times 3$
1, 2, 3, 6, 9, 18 are divisors of 18
So, {x : x ∈ N and x is a factor of 18}
$\therefore$ (ii) matches (d)
(iii) $\{-3,-2,-1,0,1,2,3\}$
$(-3)^{2}=9<16$
$(-2)^{2}=4<16$
$(-1)^{2}=1<16$
$(0)^{2}=0<16$
$(1)^{2}=1<16$
$(2)^{2}=4<16$
$(3)^{2}=9<16$
All are the given elements are integers and satisfying x2 < 16
So, (iii) matches (a)
(iv) $\{\mathrm{P}, \mathrm{R}, \mathrm{I}, \mathrm{N}, \mathrm{C}, \mathrm{A}, \mathrm{L}\}$
There are 9 letters in the word PRINCIPAL out of which P and I are repeated.
So, {x : x is a letter in the word ‘PRINCIPAL’}
$\therefore$ (iv) matches (e)
(v) $\{1\}$
Since, $1 \in N$ and $(1)^{2}=1$
So, $\left\{x: x \in N\right.$ and $\left.x^{2}=x\right\}$
$\therefore$ (v) matches (b)