如何在平方根内写单词而不使单词变成斜体？

Question

我写了$\sqrt{n^{\frac{number of factors of n}{2}}}$，但“n 的因子数”变成了斜体。有人能帮忙吗？谢谢

Answer 1

我会避免在公式中使用这样的文字。无论如何，这里有三种实现，按“丑陋-糟糕-良好”的顺序排列。

\documentclass{article}
\usepackage{amsmath}

\begin{document}

A not very nice formula that's rather difficult to read
\[
\sqrt{n^{\frac{\textup{number of factors of $n$}}{2}}}
\]
Let's try to improve it by using a slashed fraction
\[
\sqrt{n^{(\textup{number of factors of $n$})/2}}
\]
but really you should define $d(n), ν(n), τ(n) or σ_0(n)$ to be the number of factors of $n$
and type your formula as
\[
\sqrt{n^{σ_0(n)/2}}=\sqrt[4]{n^{σ_0(n)}}
\]

\end{document}

Answer 2

\documentclass[12pt]{article}
\usepackage{amsmath}
\begin{document}
    $\sqrt{n^{\frac{\text{number of factors of } n}{2}}}$
\end{document}

Answer 3

并且没有任何包装：

\documentclass[12pt]{article}
\begin{document}
    $\sqrt{n^{\frac{\mbox{\tiny number of factors of } n}{2}}}$
\end{document}

或者

\documentclass[12pt]{article}
\begin{document}
    $\sqrt{n^{\frac{\mathrm{number~of~factors~of~}n}{2}}}$
\end{document}