$$\left. \begin{array} { l } { F ( x ) = 2 x 3 } \end{array} \right.$$
$\left\{\begin{matrix}x=\frac{2x_{3}}{F}\text{, }&F\neq 0\\x\in \mathrm{C}\text{, }&x_{3}=0\text{ and }F=0\end{matrix}\right.$
$\left\{\begin{matrix}x=\frac{2x_{3}}{F}\text{, }&F\neq 0\\x\in \mathrm{R}\text{, }&x_{3}=0\text{ and }F=0\end{matrix}\right.$
