LaTeX forum ⇒ Math & Science ⇒ (solved) Aligned equations, individually numbered, all inside one pair of delimiters? Topic is solved

[Mrhnhrm]

Hi, and thanks for taking a look.

So, I am trying to make a bunch of equations that are aligned, individually automatically numbered, and all of them neatly packaged into an arbitrary set of delimiters. As they say, a picture is worth a thousand words; so, please see the attached image for a (very) schematic example of what I am trying to achieve.

Any ideas on how to do this would be kindly appreciated.

p.s. solution found here.

[Ijon Tichy]

→ https://latex.org/forum/viewtopic.php?p=93527#p93527

[Mrhnhrm]

→ https://latex.org/forum/viewtopic.php?p=93527#p93527

Many thanks. May I ask for some further explanation? I looked through the (rather concise) manual for the package cases, and I couldn't figure out how to customize the alignment. The expressions (left part of the cases environment) seem to be invariably left-aligned, and the explanations (right part of the environment) form another left-aligned column, with unnecessarily wide horizontal gap. My example renders like this:

Code: [Select all] [Expand/Collapse] [Download] ({untitled.tex})

\documentclass[]{article}
\usepackage{cases}
 
\begin{document}
 
\begin{numcases}{}
e \approx 2.72 \\
\pi \approx 3.14 \\
e\pi \approx 8.5397
\end{numcases}
 
\begin{numcases}{}
	e & $ \approx 2.72 $ \\
	\pi & $ \approx 3.14 $ \\
	e\pi & $ \approx 8.5397 $
\end{numcases}
 
\end{document}

[Mrhnhrm]

... and nailed it. Package empheq gets the job done. For example...

Code: [Select all] [Expand/Collapse] [Download] ({untitled.tex})

\documentclass[]{article}
\usepackage{amsmath}
\usepackage{empheq}
\begin{document}
\begin{subequations}
	\begin{empheq} [left=\empheqlbrace] {align}
		e & \approx 2.72 \\
		\pi & \approx 3.14 \\
		e\pi & \approx 8.5397
	\end{empheq}
\end{subequations}
 
\end{document}