\varsubsetneqThe symbol \varsubsetneq is used in mathematics to denote a subset relationship that is not equal. Specifically, it indicates that one set is a proper subset of another, meaning that all elements of the first set are contained in the second set, but the two sets are not identical. This is a negated relation because it explicitly states that the subset is not equal to the set it is contained within.
Set A is a proper subset of set B, meaning A is contained within B but A is not equal to B.
A \varsubsetneq BThe set containing elements 1 and 2 is a proper subset of the set containing elements 1, 2, and 3.
\{1, 2\} \varsubsetneq \{1, 2, 3\}Set X is a proper subset of set Y, indicating all elements of X are in Y, but X and Y are not the same set.
X \varsubsetneq Y