Chapter A.2, Problem 17P

In each of Problems 15 through 17, determine whether ${\text{b}}_j\in S_{\text{col}}\left(\text{A}\right),j=1,2.$ If so, express ${\text{b}}_j$ as a linear combination of the columns of $\text{A}$.

$\text{A}\text{=}\left(\begin{array}{cccc}1& 2& -1& 2\\ -1& 1& 2& 2\\ 0& 1& 3& 4\\ 2& 0& -1& 1\end{array}\right),b_1=\left(\begin{array}{c}4\\ -5\\ -3\\ 7\end{array}\right),b_2=\left(\begin{array}{c}0\\ 1\\ 1\\ 2\end{array}\right)$