17. a.) Show that the following vectors are linear dependent.
$\vec{v}_1 = \begin{pmatrix} -1 \ 2 \ -1 \ 0 \end{pmatrix}$, $\vec{v}_2 = \begin{pmatrix} 2 \ -4 \ 2 \ 0 \end{pmatrix}$, $\vec{v}_3 = \begin{pmatrix} -1 \ 0 \ 1 \ -1 \end{pmatrix}$, $\vec{v}_4 = \begin{pmatrix} 0 \ -2 \ 2 \ -1 \end{pmatrix}$,
b.) Let V = span{$\vec{v}_1, \vec{v}_2, \vec{v}_3, \vec{v}_4$}. Find a basis of V.
