\documentclass[12pt,a4paper]{article}
\usepackage{amsthm,amssymb,amsmath}
\usepackage{graphicx}
\usepackage[pagebackref=true,colorlinks,linkcolor=blue,citecolor=magenta]{hyperref}
\usepackage[extrafootnotefeatures]{xepersian}
\settextfont[Scale=1]{XB Zar}
\setlatintextfont[Scale=.9]{Times New Roman}
%\setdigitfont[Scale=1]{XB Zar}
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\newcommand{\maj}{مجموعه‌های مثبت درجه دوم}
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\begin{document}
در این مقاله به بررسی خواص \maj میپردازیم.
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\end{document}