How do I write the following symbol in latex?

Question

I tried writing the LaTeX formula $\overleftarrow{\underline{U}}$, but it renders in italics which is not what I am looking for.

Answer 1

You can use the mathrm tag like this: \overleftarrow{\underline{\mathrm{U}}}.

This renders:

or , if you're on dark mode :)

Make sure that in the LaTeX document preamble, you have:

\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}

Answer 2

If you dont want to add anything to your preamble

$\overleftarrow{\underline{\textrm{U}}}$

BTW, Text in math mode is defaulted to italics in latex

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