$${ x }^{ 2 } +ax+b=(x-1)(x-3)$$
$\left\{\begin{matrix}a=-\frac{4x+b-3}{x}\text{, }&x\neq 0\\a\in \mathrm{C}\text{, }&x=0\text{ and }b=3\end{matrix}\right.$
$\left\{\begin{matrix}a=-\frac{4x+b-3}{x}\text{, }&x\neq 0\\a\in \mathrm{R}\text{, }&x=0\text{ and }b=3\end{matrix}\right.$
$b=3-4x-ax$
