Question

The zeros of the polynomial x² − 2x − 3 are

(a) −3, 1
(b) −3, −1
(c) 3, −1
(d) 3, 1

Answer 1

$$\begin{gathered} \begin{array}{l}\left(\text{c}\right)3,-1\\ \begin{array}{l}\text{Let}\mathit{\text{f}}\left(x\right)=x^2-2x-3=0\\ =x^2-3x+x-3=0\end{array} \\ =x(x-3)+1(x-3)=0 \\ =(x-3)(x+1)=0 \\ =x=3\text{or}x=-1\end{array} \end{gathered}$$