# how to make a matrix small

how I can make this matrix small?

$G=\dfrac{1}{k(c_{k}^{2}+...+c^{2}_{n-1})+1} \begin{bmatrix} 2(c_{k}^{2}+...+c^{2}_{n-1})+1 & -c_{k}^{2}-...-c^{2}_{n-1}& -c_{k}^{2}-...-c^{2}_{n-1}&... & -c_{k}^{2}-...-c^{2}_{n-1}& c_{k}&c_{k+1}&...&c_{n-1}\\ -c_{k}^{2}-...-c^{2}_{n-1}& 2(c_{k}^{2}+...+c^{2}_{n-1})+1&... & -c_{k}^{2}-...-c^{2}_{n-1}&c_{k}&c_{k+1}&...&c_{n-1}\\ \vdots &\vdots &\vdots & \vdots & \vdots\\ -c_{k}^{2}-...-c^{2}_{n-1}}& -c_{k}^{2}-...-c^{2}_{n-1}&...&2(c_{k}^{2}+...+c^{2}_{n-1})+1 & c_{k}&c_{k+1}&...&c_{n-1}\\ \end{bmatrix}$

• Welcome to TSE. It is in your best interest that you post a Minimal Working Example, instead of a code snippet. Nov 10, 2019 at 23:22

I propose introducing a shortcut for the repeating expression, with an \intertext explaining the notation:

\documentclass{article}
\usepackage{ mathtools, nccmath}

\begin{document}

\begin{fleqn}
\begin{align*}
G =\mathrlap{\dfrac{1}{k(c_{k}^{2}+ \dots +c^{2}_{n-1})+1} \times{}} \1ex] &\times \begin{bmatrix} 2A_{k}+1 & -A_{k} & -A_{k} & \dots & -A_{k} & c_{k} & c_{k+1}& \dots & c_{n-1}\\ -A_{k} & 2A_{k} +1 & \dots & -A_{k} & c_{k} & c_{k+1} & \dots & c_{n-1}\\ \vdots & \vdots & \vdots & \vdots & \vdots\\ -A_{k} & -A_{k} & \dots & 2A_{k} + 1 & c_{k} & c_{k+1} & \dots &c_{n-1} \end{bmatrix}, \\ \intertext[0.5ex]{where \;A_{k} = c_{k}^{2}+ \dots +c^{2}_{n-1} } \end{align*} \end{fleqn} \end{document}  Another rudimental answer using matrix and smallmatrix with mathtools package. \documentclass[a4paper,12pt]{article} \usepackage{mathtools,amssymb} \begin{document} \[ \begin{matrix} G=\dfrac{1}{k(c_{k}^{2}+\ldots+c^{2}_{n-1})+1} \times & \\[1em] \begin{bsmallmatrix} 2(c_{k}^{2}+\ldots+c^{2}_{n-1})+1 & -c_{k}^{2}-\ldots-c^{2}_{n-1}& -c_{k}^{2}-\ldots-c^{2}_{n-1}&\ldots& -c_{k}^{2}-\ldots-c^{2}_{n-1}& c_{k}&c_{k+1}&\ldots&c_{n-1}\\ -c_{k}^{2}-\ldots-c^{2}_{n-1}& 2(c_{k}^{2}+\ldots+c^{2}_{n-1})+1&\ldots& -c_{k}^{2}-\ldots-c^{2}_{n-1}&c_{k} & c_{k+1} & \ldots &c_{n-1}\\ \vdots &\vdots &\vdots & \vdots & \vdots\\ -c_{k}^{2}-\ldots-c^{2}_{n-1} & -c_{k}^{2}-\ldots-c^{2}_{n-1}&\ldots& 2(c_{k}^{2}+\ldots+c^{2}_{n-1})+1 & c_{k} & c_{k+1}& \ldots &c_{n-1} \end{bsmallmatrix} \end{matrix}

\end{document}


You can use {bNiceMatrix} of nicematrix with the option small.

\documentclass[a4paper,12pt]{article}
\usepackage{nicematrix,amssymb}
\begin{document}

$\begin{matrix} G=\dfrac{1}{k(c_{k}^{2}+\ldots+c^{2}_{n-1})+1} \times & \\[1em] \begin{bNiceMatrix}[small] 2(c_{k}^{2}+\ldots+c^{2}_{n-1})+1 & -c_{k}^{2}-\ldots-c^{2}_{n-1}& -c_{k}^{2}-\ldots-c^{2}_{n-1}&\ldots& -c_{k}^{2}-\ldots-c^{2}_{n-1}& c_{k}&c_{k+1}&\ldots&c_{n-1}\\ -c_{k}^{2}-\ldots-c^{2}_{n-1}& 2(c_{k}^{2}+\ldots+c^{2}_{n-1})+1&\ldots& -c_{k}^{2}-\ldots-c^{2}_{n-1}&c_{k} & c_{k+1} & \ldots &c_{n-1}\\ \vdots &\vdots &\vdots & \vdots & \vdots\\ -c_{k}^{2}-\ldots-c^{2}_{n-1} & -c_{k}^{2}-\ldots-c^{2}_{n-1}&\ldots& 2(c_{k}^{2}+\ldots+c^{2}_{n-1})+1 & c_{k} & c_{k+1}& \ldots &c_{n-1} \end{bNiceMatrix} \end{matrix}$

\end{document}