[tex]\bf x=
\begin{cases}
7\\-3\\2
\end{cases}\implies
\begin{cases}
x=7\implies &(x-7)=0\\
x=-3\implies &(x+3)=0\\
x=2\implies &(x-2)=0
\end{cases}\\\\
-------------------------------\\\\
(x-7)(x+3)(x-2)=\textit{original polynomial}
\\\\\\
(x^2-4x-21)(x-2)\implies x^3-4x^2-21x-2x^2+8x+42
\\\\\\
x^3-6x^2-13x+42[/tex]
