Question:
If $p(x)=5-4 x+2 x^{2}$, find
(i) $p(0)$,
(ii) $p(3)$,
(iii) $p(-2)$
Solution:
(i) $p(x)=5-4 x+2 x^{2}$
$\Rightarrow p(0)=\left(5-4 \times 0+2 \times 0^{2}\right)$
$=(5-0+0)$
$=5$
(ii) $p(x)=5-4 x+2 x^{2}$
$\Rightarrow p(3)=\left(5-4 \times 3+2 \times 3^{2}\right)$
$=(5-12+18)$
$=11$
(iii) $p(x)=5-4 x+2 x^{2}$
$\Rightarrow p(-2)=\left[5-4 \times(-2)+2 \times(-2)^{2}\right]$
$=(5+8+8)$
$=21$