# Wide inverted breve overset

I want an inverted breve that spans the width of two symbols rather than one.

I have tried the suggestions in: inverted breve accent in math mode , and in How to put \smallsmile or \smallfrown on top of a letter.

But these were meant for inverted breve oversets that only span the width of one symbol.

Those suggestions give the top result below, whereas what I want is the bottom result below:

What is the best way to do this ?

• Also, is there a way to make my image smaller ? It's bigger than my entire text ! But I couldn't figure out how to change the size ='( – user1271772 Sep 19 '13 at 10:46
• \usepackage{yhmath} and \wideparen might be what you're looking for. – egreg Sep 19 '13 at 11:02

You can use yhmath:

\documentclass{article}
\usepackage{yhmath}
\begin{document}
$\wideparen{\Delta k}+\wideparen{x+y+z}$
\end{document}


This changes the math extension symbol font, so you may not want to do it; in this case you can just import the needed math accent

\documentclass{article}

\DeclareSymbolFont{YHlargesymbols}{OMX}{yhex}{m}{n}
\DeclareMathAccent{\wideparen}{\mathord}{YHlargesymbols}{"F3}

\begin{document}
$\wideparen{\Delta k}+\wideparen{x+y+z}$
\end{document}


Not exactly a parenthesis but...

\documentclass{article}
\usepackage{abraces}
\begin{document}
$\aoverbrace[L1R]{\triangle k}_{} \quad \aoverbrace[L1R]{\triangle k \nabla}_{} \quad \aunderbrace[l1r]{\triangle k}_{}$
\end{document}


In this case, I use stackengine package (\stackon) to stack the overset with the proper vertical separation, and the scalerel package (\hstretch) to horizontally stretch the \smallfrown to double its original width. Increasing the 2 argument will make the overset wider still.

\documentclass{article}
\usepackage{scalerel}
\usepackage{stackengine}
\usepackage{MnSymbol}
\stackMath
\begin{document}
$$\stackon[0pt]{\Delta k}{\hstretch{2}{\smallfrown}}$$
\end{document}


Here I show a wider alternative, also more rounded, and set lower upon the symbol:

\documentclass{article}
\usepackage{scalerel}
\usepackage{stackengine}
\usepackage{MnSymbol}
\stackMath\def\useanchorwidth{T}
\begin{document}
$$\stackon[-2.1pt]{\Delta k}{\vstretch{1.3}{\hstretch{2.9}{\smallfrown}}}$$
\end{document}