如何插入带有普通文本的 \Delta

Question

如果我做

The equation is \Delta I/I= k = constant,

我明白了

缺少 $ 插入。$ l.26 方程为 \Delta

Answer 1

\documentclass[border=12pt,preview]{standalone}
\usepackage{amsmath}
\begin{document}
This is the delta symbol in question $\Delta$.
\end{document}