tìm x: \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

Điều kiện xác định : $\begin{cases} x^2-4\ge0\\x-2\ne0 \end{cases}$

`<=>`$\begin{cases} \left[ \begin{array}{l}x\ge2\\x\le-2\end{array} \right.\\x\ne2 \end{cases}$ `<=>x>2` hoặc `x<=-2`

`->D`