Currently, it is not possible to use \overarc with <math>. But it seems \overarc is a standard LaTeX symbol. So no idea if the problem comes from AMS-LaTeX or elsewhere.
An acceptable workaround for the moment is to use \overset{\frown}{AB} instead.
PS and off-topic: It took me some time to find out this "Math (texvc)" component in this product. I was looking for AMS-LaTeX in other product.
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Possible Solution:
\overarc is currently not listed in the "math" extensions list about available macros.
The consent from the discussion about this topic seems to be implementing the \overarc function using the ⏜ character only for the new native MathML rendering mode.
This can be done by
- [ ] adding \overarch to the list of available macros and then
- [ ] implementing it the same way as, e.g., \overbracket, just with the 23DC character instead of 23DE.
The current workaround from this template https://en.wikipedia.org/wiki/Template:Overarc uses a <span> element, creating a curved line as text decoration in HTML. While this looks more accurate, it cannot be easily replicated using unicode characters in a <math> element. Therefore, I would suggest the approach mentioned above.
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**Version**: unspecified
**Severity**: normal
**See Also**:
https://github.com/mathjax/MathJax/issues/567