[antiframe]

So, do they write their formulas like S a b f(x)dx in their hand-written source text, but then get the LLM to convert that to \int_{a}^{b}f(x)dx? Invent their own "markup" to indicate S a b is the integral from a to b? They might as well learn \int and just use that.

I write LaTeX by hand all the time whenever I need to put any math in my notes, and depending on your use-case or field, you learn the LaTeX for that which you use often and it's faster than trying to use most tools.