In the snip, we can see that two groups of equations, aligned individually on the within-group = symbols.    \documentclass{article} \usepackage{mathtools}   \begin{document}   \begin{enumerate} \item     $$\begin{aligned}     \int x^2 \cos x \,dx     &amp;= x^2 \sin x - 2 \int x \sin x \,dx     \\ &amp;= x^2 \sin x - 2 (-x \cos x +\int \cos x \,dx)     \\ &amp;= x^2 \sin x - 2 (-x \cos x + \sin x \,dx + C)     \\ &amp;= x^2 \sin x + 2x \cos x - 2\sin x + C     \end{aligned}$$  \item     $$\begin{aligned}     \int \frac{\ln x}{x^3} \,dx     &amp;= -\frac{1}{2} \frac{\ln x}{x^2} +         \frac{1}{2} \int \frac{1}{x^3} \,dx     \\ &amp;= -\frac{\ln x}{2x^2} +         \frac{1}{2} \cdot -\frac{1}{2x^2} + C     \\ &amp;=  -\frac{\ln x}{2x^2} - \frac{1}{4x^2} + C     \\ &amp;= -\frac{1}{4x^2}(2\ln x + 1) + C     \end{aligned}$$  \end{enumerate}   \end{document}   How to align the two groups of equations on the same equal symbol "="?  Like this:    \documentclass{article}   \usepackage{mathtools} \begin{document} \begin{enumerate} \item     $$\begin{aligned}     \int x^2 \cos x \,dx     &amp;= x^2 \sin x - 2 \int x \sin x \,dx     \\ &amp;= x^2 \sin x - 2 (-x \cos x +\int \cos x \,dx)     \\ &amp;= x^2 \sin x - 2 (-x \cos x + \sin x \,dx + C)     \\ &amp;= x^2 \sin x + 2x \cos x - 2\sin x + C     \\     \\     \int \frac{\ln x}{x^3} \,dx     &amp;= -\frac{1}{2} \frac{\ln x}{x^2} +         \frac{1}{2} \int \frac{1}{x^3} \,dx     \\ &amp;= -\frac{\ln x}{2x^2} +         \frac{1}{2} \cdot -\frac{1}{2x^2} + C     \\ &amp;=  -\frac{\ln x}{2x^2} - \frac{1}{4x^2} + C     \\ &amp;= -\frac{1}{4x^2}(2\ln x + 1) + C     \end{aligned}$$ \end{enumerate} \end{document}   In this approach, the numbers generated by enumerate are missing, so I'm wondering are there better ways.
I have a problem regarding alignment for my equations.  This dummy program shows the problem:  \documentclass{article} \usepackage{amsmath} \begin{document}  \begin{enumerate}     \item First do this     \begin{align}     c^2 &amp;= a^2 + b^2     \end{align}      \item Then do this      \begin{align}     variable &amp;= c^2     \end{align} \end{enumerate}  \end{document}     I would like the = to be aligned under each other, but still be able to list them inside the enumerate.  Any suggestions?
Can't install wine from winehq.org on Ubuntu (actually Lubuntu) 18.04 LTS I have followed all the instructions on .  In particular, I have run the following commands: sudo dpkg --add-architecture i386  wget -nc https://dl.winehq.org/wine-builds/winehq.key sudo apt-key add winehq.key sudo apt-add-repository 'deb https://dl.winehq.org/wine-builds/ubuntu/ bionic main'   The first three of the above seemed to work fine.  However, the last command gives me the following error: Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  winehq-stable : Depends: wine-stable (= 5.0.0~bionic) E: Unable to correct problems, you have held broken packages.  I'm running Lubuntu 18.04.3 on a USB live stick.  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