My matrix goes off the page. Usually, when I work with simple equations, I use the code \begin{eqnarray}\end{eqnarray*} to align equations vertically by the equal sign.
Do you know if I can do something similar with the following matrix code? \begin{eqnarray}\end{eqnarray*} doesn't work here.
\documentclass[paper=a4, fontsize=11pt]{scrartcl}
\usepackage{amsmath}
\usepackage{enumitem}
\begin{document}
%PROBLEM 2
Let $\textbf{a}' = \begin{bmatrix}
3 & 6 &-3 & 5 & 9& 2 \\
\end{bmatrix}$. Find \textbf{a}$'$\textbf{a} and \textbf{aa}$'$.
\textbf{a}$'$ is the transpose of $\textbf{a} = \begin{bmatrix}
3 \\ 6 \\-3 \\ 5 \\ 9\\ 2 \\
\end{bmatrix}$
\[\textbf{a}'\textbf{a} = \begin{bmatrix}
3 & 6 &-3 & 5 & 9& 2 \\
\end{bmatrix} \cdot \begin{bmatrix}
3 \\ 6 \\-3 \\ 5 \\ 9\\ 2 \\
\end{bmatrix} = \begin{bmatrix}
3^2 + 6^2 + (-3)^2 + 5^2 + 9^2 + 2^2 \\
\end{bmatrix} =[164] \]
\[\textbf{aa}' = \begin{bmatrix}
3 \\ 6 \\-3 \\ 5 \\ 9\\ 2 \\
\end{bmatrix}\cdot \begin{bmatrix}
3 & 6 &-3 & 5 & 9& 2 \\
\end{bmatrix} = \begin{bmatrix}
3^2& 3\cdot 6 & 3\cdot (-3) & 3\cdot 5 & 3\cdot 9 & 3\cdot 2 \\
6\cdot 3& 6^2 & 6\cdot (-3) & 6\cdot 5 & 6\cdot 9 & 6\cdot 2 \\
(-3)\cdot 3& (-3)\cdot 6 & (-3)^2 & (-3)\cdot 5 & (-3)\cdot 9 & (-3)\cdot 2 \\
5\cdot 3& 5\cdot 6 & 5\cdot (-3) & 5^2 & 5\cdot 9 & 5\cdot 2 \\
9\cdot 3& 9\cdot 6 & 9\cdot (-3) & 9\cdot 5 & 9^2 & 9\cdot 2 \\
2\cdot 3& 2\cdot 6 & 2\cdot (-3) & 2\cdot 5 & 2\cdot 9 & 2^2 \\
\end{bmatrix} \\=\begin{bmatrix}
9& 18 & 9 & 15 & 27 & 6 \\
18& 36 & -18 & 30 & 54 & 12 \\
-9& -18 & 9 & -15 & 27 & -6 \\
15& 30 & 15 & 10 & 45 & 10 \\
27& 54 & 27 & 45 & 81 & 18 \\
6& 12 & 6 & 10 & 18 & 4 \\
\end{bmatrix} \]
\end{document}
align*– Sep 18 '14 at 14:23