没有在乳胶中显示孟加拉方程作为输出

Question

\documentclass[a4paper,12pt]{book}
\usepackage[inner=1.5cm, outer=1.5cm, top=1.5cm, bottom=1.5cm]{geometry}
\tracinglostchars=2
\usepackage[bidi=basic,layout=sectioning]{babel}
\usepackage{fontspec}

\babelprovide[onchar=fonts ids]{bengali}
\babelprovide[import,main]{english}
\defaultfontfeatures{Scale=MatchLowercase, Ligatures=TeX, Renderer=HarfBuzz}

%% These fonts are abailable at: https://www.google.com/get/noto/
\babelfont{rm}
[Ligatures=Common,Scale=1.0,Language=Default]{Times New Roman}
\babelfont{sf}
[Language=Default]{Times New Roman}
\babelfont{tt}
[Language=Default]{Times New Roman}
\babelfont[bengali]{rm}
[Language=Default]{Noto Serif Bengali}
\babelfont[bengali]{sf}
[Language=Default]{Noto Sans Bengali}
\babelfont[bengali]{tt}
[Language=Default]{Noto Sans Bengali UI}

\babeltags{english=english}
\babeltags{bengali=bengali}
\usepackage{multicol}

\usepackage{amsmath,amssymb,amsfonts}
%\usepackage{unicode-math}


%%%%%%%%%%%%%%%%for image
\usepackage{wrapfig}
\usepackage{graphicx}
\usepackage{float} 
\usepackage{caption}
\usepackage{subcaption}

%%for drawining
\usepackage{tikz}
\usetikzlibrary{patterns,shapes.arrows,calc}

%%%for table 
\usepackage{tabularray}







\begin{document}    
        $e=\frac{ সংঘাতের পর বস্তুদ্বয়ের অপসারণ বেগ }{সংঘাতের পূর্বে বস্তুদ্বয়ের আগমন বেগ}$     
    
\end{document}

Answer 1

数学字体不知道如何处理孟加拉语。我建议暂时切换到文本模式：

\documentclass[a4paper,12pt]{book}
\usepackage[inner=1.5cm, outer=1.5cm, top=1.5cm, bottom=1.5cm]{geometry}
\tracinglostchars=2
\usepackage[bidi=basic,layout=sectioning]{babel}
\usepackage{fontspec}

\babelprovide[onchar=fonts ids]{bengali}
\babelprovide[import,main]{english}
\defaultfontfeatures{Scale=MatchLowercase, Ligatures=TeX, Renderer=HarfBuzz}

%% These fonts are abailable at: https://www.google.com/get/noto/
\babelfont{rm}
[Ligatures=Common,Scale=1.0,Language=Default]{Times New Roman}
\babelfont{sf}
[Language=Default]{Times New Roman}
\babelfont{tt}
[Language=Default]{Times New Roman}
\babelfont[bengali]{rm}
[Language=Default]{Noto Serif Bengali}
\babelfont[bengali]{sf}
[Language=Default]{Noto Sans Bengali}

\babeltags{english=english}
\babeltags{bengali=bengali}

\usepackage{amsmath,amssymb,amsfonts}

\begin{document}
        
 $e=\frac{\textrm{সংঘাতের পর বস্তুদ্বয়ের অপসারণ বেগ }}{\textrm{সংঘাতের পূর্বে বস্তুদ্বয়ের আগমন বেগ}}$

\end{document}