45

I have seen several posts on how to remove the qed symbol in a proof, but that affects all proof environments. I would like to know how to remove the qed symbol in a particular proof because I have one proof inside another.

Alan Munn
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Juan Quispe
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    If you write \phantom\qedhere anywhere in the proof the qed symbol disappears. But I don't know if it's the best way of doing that. – Manuel Dec 25 '12 at 19:43
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    Certainly, this works, but I have a proof in another, produces an excessive vertical space to the next paragraph. – Juan Quispe Dec 25 '12 at 20:03
  • That's why this is not optimal. You have to find where to put it with no problems manually. i.e., If you put it at the end of a paragraph, it works fine, but still manual. Wait until someone gives you an universal way of doing it. – Manuel Dec 25 '12 at 20:09
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    If you need a block with Proof at the beginning why don't you fake it? For example \par\noindent\textit{Proof.}\. – Sigur Dec 25 '12 at 20:10
  • Well, I found a way to do it but not very elegant. Thanks to Manuel, and all of you, for Replied. I added only \vspace{-0.5cm}\phantom\qedhere after the inner proof. – Juan Quispe Dec 25 '12 at 20:50

3 Answers3

49

Just locally change the meaning of \qedsymbol:

\documentclass{article}
\usepackage{amsthm}
\begin{document}
\begin{proof}
This has the QED symbol.
\end{proof}
\begin{proof}\renewcommand{\qedsymbol}{}
This hasn't.
\end{proof}
\begin{proof}
And this has it again.
\end{proof}
\end{document}

enter image description here

You can make a new environment for "inner proofs":

\newenvironment{innerproof}
 {\renewcommand{\qedsymbol}{}\proof}
 {\endproof}

which will do the same.

egreg
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    Thanks for response. This works, but produce extra vertical space for the next paragraph when it has a proof inside another. Thanks a lot. – Juan Quispe Dec 25 '12 at 20:54
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    @JuanQuispe Some way or another you have to tell your reader when the inner proof ends – egreg Dec 25 '12 at 20:58
  • Yes. well, I found a way to do it, but is not very elegant. Merry Christmas – Juan Quispe Dec 25 '12 at 21:01
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    @JuanQuispe: Can you tell here? I think it would be interesting for other people also ... – Mensch Dec 25 '12 at 21:14
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    I had the same issue with extra vertical space as @JuanQuispe and inserted \renewcommand{\qed}{} instead of \renewcommand{\qedsymbol}{} to get rid of the QED symbol. Not sure if this is a perfect solution but so far it seems to work. Also see this post for the details of the \qedsymbol, \qed etc. commands. (UPDATE: I just noticed that barbara beeton suggested the same solution in her answer below.) – balu Mar 08 '20 at 20:12
  • @balu If you end your “no qed” proof with a display, you still need \qedhere. – egreg Mar 08 '20 at 22:12
34

if you're using amsthm, you can do this:

\documentclass{article}
\usepackage{amsthm}
\begin{document}
\begin{proof}
This has the QED symbol.
\end{proof}
\begin{proof}\let\qed\relax
This hasn't.
\end{proof}
\begin{proof}
And this has it again.
\end{proof}
\end{document}

(thanks to egreg for providing an example that could be cribbed easily.)

barbara beeton
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7

I handle such cases as follows.

\begin{proof}\phantom{\qedhere}
No QED symbol.
\end{proof}

\begin{proof}
QED symbol.
\end{proof}

\begin{proof}
\begin{itemize}
\item \textellipsis
\item QED symbol at the end of the final item. \qedhere
\end{itemize}
\end{proof}

\begin{proof}\phantom{\qedhere}
\begin{equation}
\text{QED symbol at the end of the final equation.}\tag*{\qed}
\end{equation}
\end{proof}

enter image description here

bkarpuz
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  • Not tested, but I suspect that if the last line of a proof finishes very close to the end of the line, \phantom{\qedhere} may result in an extra blank line. – barbara beeton Feb 14 '23 at 16:40