## Linear Algebra and Its Applications (5th Edition)

a) $\left[ {\begin{array}{cc} 5\\ 1 \end{array} } \right]$ b) $\left[ {\begin{array}{cc} -1\\ 4 \end{array} } \right]$
We want to compute $u+v$ and $u-2v$ for $u= \left[ {\begin{array}{cc} 3\\ 2\\ \end{array} } \right]$ and $v= \left[ {\begin{array}{cc} 2\\ -1 \end{array} } \right]$. $u+v=\left[ {\begin{array}{cc} 3\\ 2\\ \end{array} } \right]+\left[ {\begin{array}{cc} 2\\ -1 \end{array} } \right]=\left[ {\begin{array}{cc} 5\\ 1 \end{array} } \right]$ $u-2v=\left[ {\begin{array}{cc} 3\\ 2\\ \end{array} } \right]-2\left[ {\begin{array}{cc} 2\\ -1 \end{array} } \right]=\left[ {\begin{array}{cc} -1\\ 4 \end{array} } \right]$