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I'm trying to formatting those equation, but every time remains some space in the middle.
Can you help me please?
(using Overleaf)

\subsection*{Criterio di classificazione dei punti critici}
Sia $C \subseteq \mathbb{R}^n$ un insieme compatto,\\
Sia $f: C \rightarrow \mathbb{R}$, continua in C e ...

Thank you for the answear.

With "minimal working example" do you mean a section of my math notes?

Where can I find the .toc extension file?

Thank you again

Hi.
I'm new to Latex, I discover it reading on this page, casually.
I have recently start to use it to rewrite math notes, downloading MiKTeX package of programs. I have a problem with an error:
I didn't managed to solve it reading online or trying correctiong it myself. I'm stuck.

I'm using ...