While I was trying to improve my latest document with respect to its `\qed`

symbols at the end of `amsthm`

's `proof`

environment i came across an interesting point. Assume the proof ends with some formula, that is finally representing the form the lemma/theorem proposes.

Something like

```
\documentclass{scrartcl}
\usepackage[fleqn]{amsmath}
\usepackage{amsthm,amstext,amsfonts,bm,amssymb}
\begin{document}
\begin{proof}
...
\begin{equation}
\begin{split}
A&= B \\
&= C\\
&= D&\qedhere
\end{split}
\end{equation}
\end{proof}
\end{document}
```

While using `\qedhere`

just in `equation`

or `align`

would put the symbol below any number (or at least to that side for `euqation*`

), here the symbol is placed far to the left, even with using the additional column with `&`

. Putting it after `\end{split}`

would center it vertically with respect to the three columns, so my question is

How can I get the `\qed`

symbol to the bottom right (text border) of an (equation-)split environment?

Where I would prefer a global solution for all `split`

s where I mention `\qedhere`

at the end.

## Best Answer

the best approach in this particular case is to use

`align*`

, as that behaves well with`\qedhere`

since each line is treated separately. (any of the multi-line options that treats lines separately should work equally well.)this isn't always ideal --

`cases`

, for example, will always force the tombstone to the center vertically -- but the request has been made often enough to place the tombstone on the last line, that it should be considered as a possible option. i am adding it to the formal list of requests.as noted elsewhere, with flush left equations and equation numbers on the right, there is a built-in conflict. that is why ams document classes default to using equation numbers on the left.