如何将数学模式与文本的其余部分合并在一起

Question

如何将数学模式包含在文本的其余部分中？目前它很尴尬。以下是代码：

\documentclass[twocolumn]{article}

\usepackage{booktabs, makecell, tabularx}
\renewcommand\theadfont{\normalsize}
\renewcommand\theadgape{}
\setcellgapes{2pt}
\newcolumntype{L}{>{\raggedright\arraybackslash}X}
\usepackage{caption}
\usepackage{textcomp}
\usepackage{graphicx}
\raggedbottom
\usepackage{amsmath,geometry}
\usepackage{rotating}
\usepackage{booktabs, makecell}
\usepackage[referable]{threeparttablex}
\usepackage{siunitx}
\usepackage[skip=1ex]{caption}
\usepackage{upquote}
\usepackage{balance}
\usepackage[lite]{mtpro2} % Times Roman math font
\usepackage{float}
\usepackage{wasysym}
\title{\LARGE \bf ECON 425 Term Paper}

\begin{document}  

 \section{Conclusions}
 To the credit of this work, few studies include control variables 
 such as gender, race, or age. In this study, it was found that 
 male CEOs are expected to earn less than female CEOs. With regards 
 to age, the coefficients on age and \[ \textrm{age}^2 \] show, as 
 expected, increasing then decreasing levels of compensation. 

\end{document}

Answer 1

为什么不简单呢\textsuperscript？

\documentclass[twocolumn]{article}

\usepackage{booktabs, makecell, tabularx}
\renewcommand\theadfont{\normalsize}
\renewcommand\theadgape{}
\setcellgapes{2pt}
\newcolumntype{L}{>{\raggedright\arraybackslash}X}
\usepackage{caption}
\usepackage{textcomp}
\usepackage{graphicx}
\raggedbottom
\usepackage{amsmath,geometry}
\usepackage{rotating}
\usepackage[referable]{threeparttablex}
\usepackage{siunitx}
\usepackage[skip=1ex]{caption}
\usepackage{upquote}
\usepackage{balance}
\usepackage{mathptmx}% replaces mtpro2, which is not installed on my system
%\usepackage[lite]{mtpro2} % Times Roman math font
\usepackage{float}
\usepackage{wasysym}
\title{\LARGE \bf ECON 425 Term Paper}

\begin{document}

 \section{Conclusions}

    To the credit of this work, few studies
    include control variables such as gender, race, or age. In this study, it was found that male CEOs are expected to earn less than female CEOs. With regards to age, the coefficients on age and age\textsuperscript{2} show, as expected, increasing then decreasing levels of compensation.

\end{document}