I want to put an undertilde accent on symbols in math mode.

Things I have tried

I’m fairly new to LaTeX / MathJax and find it anything much more complex than \frac{1}{2} very confusing. It seems to be possible to create an undertilde accent in other packages in LaTeX, but I have no clue how to transfer that over to Obsidian.

I have tried the following commands to no success: \~{x}, \tilde{x}, \utilde{x}, `undertilde{x}, \underaccent{\wtilde}{x}`. The best I have managed to achieve is copy/pasting the unicode undertilde symbol, but it doesn’t even line up correctly $Ḭ$.

After many wasted hours of Googling, I think I need help from someone who knows more than I do because I am so confused. Does anyone know how to do this?

Welcome to LaTex my friend. Do not be disheartened. You will find it very rewarding if you persist. Try this - \underset{\sim}{\textbf{x}}. Obviously, you can remove the \textbf command if you don’t want it in bold.

Not entirely sure about the ability to move the tilde up but you could try undersetting the line instead which will bring the dash down and inline with the tilde instead of moving the tilde up? Not sure if this would help in your situation…