Just for fun. Can you make this equation as pretty as possible?
\documentclass{article}
%
\usepackage{amsmath}
\usepackage{palatino}
\usepackage{mathpazo}
\usepackage{bm}
%
\begin{document}
$\delta\int_{t_1}^{t_2}\mathcal{L}(\bm{q},\bm{\dot{q}})dt=0$
\end{document}
It should be pretty when printed on a whole page. So be careful to the spacings between the symbols.
\scaleboxcan be employed. – Steven B. Segletes Aug 02 '17 at 02:54\newcommand{\diff}{\mathop{}\!d}and use\diff tinstead ofdt; it should be\dot{\bm{q}}; define\newcommand{\vari}{\mathop{}\!\delta\check@for@int}and\newcommand{\check@for@int}{\@ifnextchar{\int}{\mkern-6mu}{}}(requires\makeatletterand\makeatother). Then try\vari\int.... – egreg Aug 02 '17 at 08:36