Answer
a) $\left[ {\begin{array}{cc}
-4\\
1
\end{array} } \right]$
b) $\left[ {\begin{array}{cc}
5\\
4
\end{array} } \right]$
Work Step by Step
Vector addition works by adding up components of vectors:
$$u+v=
\begin{bmatrix}-1 \\ 2\end{bmatrix}
+
\begin{bmatrix}-3 \\ -1\end{bmatrix}
=
\begin{bmatrix}-4 \\ 1\end{bmatrix}
$$
Vector-Scalar Multiplication works by multiplying the scalar by each component of the vector:
$$u-2v=
\begin{bmatrix}-1 \\ 2\end{bmatrix}
+
\begin{bmatrix}6 \\ 2\end{bmatrix}
=
\begin{bmatrix}5 \\ 4\end{bmatrix}
$$