> [!NOTE] Definition (Set Complement) > Let $U$ be a [[Sets|set]]. Let $A$ be a [[Subsets|subset]] of $U.$ The complement of $A,$ denoted $A^{c},$ is the [[Set Difference|difference]] $U-A$: that is $A^{c}=\{ x \in U \mid x \not \in A \}.$