題組內容

2. Let

$$\mathbf {A} = \left[ \begin{array}{c c c c} 1 & - 2 & - 1 & 2 \\ 2 & - 1 & 3 & 1 \\ - 1 & 1 & - 1 & - 1 \end{array} \right].$$


(a)(10%) Find a basis for the row space of \( \mathbf{A} \) and a basis for the null space of \( \mathbf{A} \).