How do I add a $\square$ at the end of a paragraph and align it to the right, as if it were the end of proof (not via \begin{proof} !)

Question

How do I add a \square (or anything else) at the end of a paragraph and align it to the right as if it is the end of proof (without \begin{proof} at the beginning). I don't want to see the "proof" at the beginning.

And at the same time, I only need a local/temporary change. I don't want to change the "proof" environment at the beginning. I still want to use \begin{proof} normally in other places

egreg · Accepted Answer · 2022-09-09T22:14:35.057

You just declare \qed at the end of the paragraph, which is essentially what \end{proof} does automatically (with some more bells and whistles you don't need for your situation).

\documentclass{article}
\usepackage{amsthm}
\begin{document}
A paragraph with a QED symbol at the far end. Let's go on with
nonsense words just to get a few lines. Let's go on with
nonsense words just to get a few lines. Let's go on with
nonsense words just to get a few lines.\qed
\end{document}

You can locally change the QED symbol. I suggest a special command for the task you want (a triangle instead of the square).

\documentclass{article}
\usepackage{amsthm}
\newcommand{\triangleqed}{%
  \begingroup
  \renewcommand{\qedsymbol}{\ensuremath{\triangle}}%
  \qed
  \endgroup
}
\begin{document}
A paragraph with a QED symbol at the far end. Let's go on with
nonsense words just to get a few lines. Let's go on with
nonsense words just to get a few lines. Let's go on with
nonsense words just to get a few lines.\qed
A paragraph with a QED symbol at the far end. Let's go on with
nonsense words just to get a few lines. Let's go on with
nonsense words just to get a few lines. Let's go on with
nonsense words just to get a few lines.\triangleqed
A paragraph with a QED symbol at the far end. Let's go on with
nonsense words just to get a few lines. Let's go on with
nonsense words just to get a few lines. Let's go on with
nonsense words just to get a few lines.\qed
\end{document}

Thanks, and what is the easiest way to replay \qed with other symbols like $\triangle$ temporally that still do the same job (pushed to the end of a line)? — No One, Sep 09 '22 at 22:03
@NoOne You should edit the question to also reflect the added requirement. — egreg, Sep 09 '22 at 22:23

score 2 · Answer 2 · edited Sep 10 '22 at 04:31

2

Do you mean like this:

\documentclass{article}
\usepackage{lipsum}
\usepackage{amssymb}
\begin{document}
\lipsum[2]
  \unskip\nobreak\hfill $\square$
\end{document}

Output:

This shows how output has been produced:

edited Sep 10 '22 at 04:31

wipet

74,238

answered Sep 09 '22 at 21:10

Marco Moldenhauer

540

2

You perhaps meant not to have a blank line before \hfill$\square$. However, this doesn't guarantee that the square falls at the end of the line. And the symbol used by amsthm is not $\square$ . – egreg Sep 09 '22 at 21:23
1

Yes, e.g. with \lipsum[8] the square would go to the start of the next line. – dexteritas Sep 09 '22 at 21:28

How do I add a $\square$ at the end of a paragraph and align it to the right, as if it were the end of proof (not via \begin{proof} !)

2 Answers2