Question

Check whether $-3$ and $3$ are the zeroes of the polynomial $x^2-9$.

Answer 1

Let $p\left(x\right)=x^2-9$
Zeroes of the polynomial $p\left(x\right)=0$
$\Rightarrow x^2-9=9$
$\Rightarrow x^2=9$
$\Rightarrow x=\sqrt{9}$
$\Rightarrow x=\pm 3$
$\Rightarrow x=3,-3$
$\therefore$ Zeroes of the polynomial $p\left(x\right)$ are $-3$ and $3.$