I have a mathematical exercise written in LaTeX and it seems ugly to me. It is ok to ask what would be the best (and most beautiful) way to typeset it?
The exercise in question is the following:
\documentclass{article}
\usepackage[top=0.7in, bottom=1.2in, left=0.8in, right=0.8in]{geometry}
\usepackage{parskip}
\setlength{\parindent}{0cm}
\usepackage{amsmath}
\usepackage{unicode-math}
\usepackage{fontspec}
\usepackage[greek,english]{babel}
\setmainfont[Ligatures=TeX, Extension=.otf, UprightFont=*, BoldFont=*Bold, ItalicFont=*It, BoldItalicFont=*BoldIt, Mapping=tex-text]{GFSArtemisia}
\setsansfont[Mapping=tex-text]{GFSArtemisia.otf}
\setmathfont{latinmodern-math.otf}
\setmathfont[range=\varnothing]{Asana-Math.otf}
\setmathfont[range=\int]{latinmodern-math.otf}
\begin{document}
\begin{align*}
&\frac{d H}{d p}= -(1-2\cdot \epsilon\cdot p+\epsilon)\log(p-2\cdot \epsilon\cdot p-a\cdot p+\epsilon)-a\cdot \log(a)-\\
&(1-p+2\cdot \epsilon\cdot p+a\cdot p-\epsilon-a)\log (1-p+2\cdot \epsilon\cdot p+a\cdot p-\epsilon-a)=\\
&=-(1-e\cdot \epsilon-a)\log(p-2\cdot \epsilon\cdot p-a\cdot p+\epsilon)-\\
&(1-2\cdot \epsilon\cdot p-a\cdot p)\cdot\frac{1}{-2\cdot \epsilon\cdot p-a\cdot p+\epsilon}\cdot (1-2\cdot \epsilon-a)-\\
&(-1+2\cdot \epsilon+a)\log(1-p-2\cdot \epsilon\cdot p+a\cdot p-\epsilon-a)-\\
&(1-p-2\cdot \epsilon\cdot p+a\cdot p-\epsilon-a)\cdot \frac{1}{1-p+2\cdot \epsilon\cdot p+a\cdot p- \epsilon-a}\cdot (-1+2\cdot \epsilon+a)=\\
&-(1-2\cdot \epsilon -a)\log(p-2\cdot \epsilon\cdot p-a\cdot p+\epsilon)-(1-2\cdot \epsilon-a)-\\
&(-1+2\cdot \epsilon+a)\log(1-p+2\cdot \epsilon\cdot p+a\cdot p-\epsilon-a)-(-1+2\cdot \epsilon+a)=\\
&-(1-2\cdot \epsilon-a)[\log(p-2\cdot \epsilon\cdot p-a\cdot p+\epsilon)+\log(1-p+2\cdot \epsilon\cdot p+a\cdot p-\epsilon-a)]
\end{align*}
\end{document}
$H = 1 - 2 \epsilon - a$
at the top of the exercise, and then using that throughout. It shortens it quite considerably.