增加衍生品的规模

Question

\documentclass{article}
\usepackage[utf8]{inputenc}
\begin{document}
The vertical differential velocity is 

$\delta v_2 = v_{2C} - v_{2A} = v_2(x + \delta x , y) - v_2(x,y) \approx 
\delta x \frac{\partial v_2}{\partial x} $. 
\end{document}

我怎样才能使导数看起来更大而不是与句子中的单词大小相同？

谢谢！

Answer 1

通常，如此大的表达式应该设置为显示数学环境，而不是使用内联数学的段落：

\documentclass{article}
\usepackage[utf8]{inputenc}
\begin{document}

\section{inline}

The vertical differential velocity is 

$\delta v_2 = v_{2C} - v_{2A} = v_2(x + \delta x , y) - v_2(x,y) \approx 
\delta x \frac{\partial v_2}{\partial x} $. 


\section{display}

The vertical differential velocity is 
\[\delta v_2 = v_{2C} - v_{2A} = v_2(x + \delta x , y) - v_2(x,y) \approx 
\delta x \frac{\partial v_2}{\partial x} \mbox{.}\] 


\end{document}