A big veebar - how to produce it?

Question

guys.

I'm writing some logic equations and I need something like this:

I produce this symbol through the following piece of code:

\begin{equation} \underline{\bigvee^{\forall R_{I}}}R_{I}(x,y) \end{equation}

However, when I have wider limits, this ugly thing happens:

The question is: is there any way to produce a "big" \veebar symbol where the underbar has the same length of the "V" (more likely the first picture)?

Any ideas are welcomed! Thanks in advance!

Answer 1

Welcome! Just declare a new math operator that can have limits. This can be done with the starred version of \DeclareMathOperator, \DeclareMathOperator*.

\documentclass{article}
\usepackage{amsmath}
\DeclareMathOperator*{\ubigvee}{\underline{\bigvee}}
\begin{document}
\begin{equation} 
\ubigvee^{\forall R_{I}}R_{I}(x,y) \quad
\ubigvee^{\forall R_{I},x,y}R_{I}(x,y) 
\end{equation}
\end{document}