The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 1\\[1 em]x_2 &= -1 \end{aligned} $$Step 1:
Combine like terms:
$$ x^2+ \color{blue}{2} \color{blue}{-3} = x^2 \color{blue}{-1} $$Step 2:
The solutions of $ x^2-1 = 0 $ are: $ x = -1 ~ \text{and} ~ x = 1$.
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