# How can I make a matrix equation smaller in way that it fits in one line on a page?

I have the following matrix equation written in latex.

\documentclass[a4paper, 12 pt]{report}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage[top=1in, bottom=1in, left=1.5in, right=1in]{geometry}
\begin{document}

$\begin{bmatrix} \frac{-\beta_2}{\bx} & \frac{\beta_1}{\bx} \\ \addlinespace -\frac{1}{\bx} & \frac{1}{\bx} \end{bmatrix} \begin{bmatrix} 1 & -\beta_1 \\ 1 & -\beta_2 \end{bmatrix} \begin{bmatrix} \mathrm{q}_t \\ \mathrm{p}_t \end{bmatrix} + \begin{bmatrix} \frac{-\beta_2}{\bx} & \frac{\beta_1}{\bx} \\ \addlinespace -\frac{1}{\bx} & \frac{1}{\bx} \end{bmatrix} \begin{bmatrix} -\alpha_1 & -\gamma_1 & 0 \\ -\alpha_2 & 0 & -\gamma_2 \end{bmatrix} \begin{bmatrix} 1 \\ \mathrm{i}_t \\ \mathrm{r}_t \end{bmatrix} = \begin{bmatrix} \frac{-\beta_2}{\bx} & \frac{\beta_1}{\bx} \\ \addlinespace -\frac{1}{\bx} & \frac{1}{\bx} \end{bmatrix} \begin{bmatrix} \varepsilon_{1t} \\ \varepsilon_{2t} \end{bmatrix}$

\end{document}


The output is provided below. This does not appear in one line. How can I make it smaller such that it appears in one line?

• you have not provided an example we can test, in particular we do not know how big the line is. But note you are forcing over-large fractions by using dfrac rather than frac Dec 5, 2020 at 13:17
• I have edited the codes. Dec 5, 2020 at 13:36

I suggest you replace the fraction terms with simpler terms, such as \kappa_0, \kappa_1, and \kappa_2.

\documentclass{article}
\usepackage[margin=2.5cm]{geometry} % set textblock parameters suitably
\usepackage{amsmath} % for 'bmatrix' env.
\begin{document}
Put $\kappa_0=1/(\beta_1-\beta_2)$, $\kappa_1=\beta_1/(\beta_1-\beta_2)$,
and $\kappa_2=\beta_2/(\beta_1-\beta_2)$. Then
$\begin{bmatrix} -\kappa_2 & \kappa_1 \\ -\kappa_0 & \kappa_0 \end{bmatrix} \begin{bmatrix} 1 & -\beta_1 \\ 1 & -\beta_2 \end{bmatrix} \begin{bmatrix} \mathrm{q}_t \\ \mathrm{p}_t \end{bmatrix} + \begin{bmatrix} -\kappa_2 & \kappa_1 \\ -\kappa_0 & \kappa_0 \end{bmatrix} \begin{bmatrix} -\alpha_1 & -\gamma_1 & 0 \\ -\alpha_2 & 0 & -\gamma_2 \end{bmatrix} \begin{bmatrix} 1 \\ \mathrm{i}_t \\ \mathrm{r}_t \end{bmatrix} = \begin{bmatrix} -\kappa_2 & \kappa_1 \\ -\kappa_0 & \kappa_0 \end{bmatrix} \begin{bmatrix} \varepsilon_{1t} \\ \varepsilon_{2t} \end{bmatrix}\,.$

\end{document}

• This solution also has the advantage to simplify the human analysis of the calculus. Dec 5, 2020 at 13:53