Answer
$v=\left[\begin{array}{l}
1\\
3\\
2
\end{array}\right] $.
Reason: Theorem 1.
Work Step by Step
Theorem 1, p.196
If $v_{1},v_{2}...,v_{p}$ are in a vector space $V$, then
Span $\{v_{1},v_{2}...,v_{p}\}$ is a subspace of V.
-------------
$\left[\begin{array}{l}
s\\
3s\\
2s
\end{array}\right]=s\left[\begin{array}{l}
1\\
3\\
2
\end{array}\right]$
$v=\left[\begin{array}{l}
1\\
3\\
2
\end{array}\right]\in \mathbb{R}^{3}$ and $H=$Span$\{\left[\begin{array}{l}
1\\
3\\
2
\end{array}\right]\}$, so by theorem 1,
$H$ is a subspace of $ \mathbb{R}^{3}$.
