%% %% An UIT Edition example %% %% Example 05-01-2 on page 72. %% %% Copyright (C) 2010 Herbert Voss %% %% It may be distributed and/or modified under the conditions %% of the LaTeX Project Public License, either version 1.3 %% of this license or (at your option) any later version. %% %% See http://www.latex-project.org/lppl.txt for details. %% %% %% ==== % Show page(s) 1 %% \documentclass[]{exaarticle} \pagestyle{empty} \setlength\textwidth{375.57637pt} \setlength\parindent{0pt} \StartShownPreambleCommands \usepackage{amsmath,xcolor} \StopShownPreambleCommands \begin{document} \begin{align*} y &= 2x^2 -3x +5\\\nonumber & \hphantom{= \ 2\left(x^2-\frac{3}{2}\,x\right. }% \textcolor{blue}{\overbrace{\hphantom{+\left(\frac{3}{4}\right)^2- % \left(\frac{3}{4}\right)^2}}^{=0}}\\[-11pt] &= 2\left(\textcolor{red}{% \underbrace{x^2-\frac{3}{2}\,x + \left(\frac{3}{4}\right)^2}}% \underbrace{-\left(\frac{3}{4}\right)^2 + \frac{5}{2}}\right)\\ &= 2\left(\qquad\textcolor{red}{\left(x-\frac{3}{4}\right)^2} \qquad + \ \frac{31}{16}\qquad\right)\\ y\,\textcolor{blue}{\mathrel{-}\frac{31}{8}} &= 2\left(x\,\textcolor{cyan}{\mathrel{-}\frac{3}{4}}\right)^2% \end{align*} \end{document}