Dear Bashir,

you can use it:

\documentclass[12pt]{article} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb} \begin{document} Properly resize variable: $x$ $\scriptscriptstyle{x}$ Properly resize matrix: $\begin{bmatrix}a & b\\ c & d\end{bmatrix}$ $\scriptscriptstyle{\begin{bmatrix}a & b\\ c & d\end{bmatrix}}$ Improperly resize matrix: $\begin{bmatrix}a & b\\ c & d\end{bmatrix}$ $\scriptsize{\begin{bmatrix}a & b\\ c & d\end{bmatrix}}$ \end{document}

P.S. by changing the value of point you can control the size of matrix.