\smallsetminusThe \smallsetminus command in LaTeX is used to denote the set-theoretic difference between two sets. It is a binary operator that is often used in mathematical expressions to indicate the elements that belong to one set but not to another.
The set of elements in A that are not in B.
A \smallsetminus BThe set of all real numbers that are not rational numbers, i.e., the irrational numbers.
\mathbb{R} \smallsetminus \mathbb{Q}The set S excluding the element x.
S \smallsetminus \{x\}