Let $P$ be the set of all subsets of a given set $X$. Show that $\cup: P \times P \rightarrow P$ given by $(A, B) \rightarrow A \cup B$ and $\cap: P \times P \rightarrow P$ given by $(A, B) \rightarrow A \cap B$ are binary operations on the set $P$.

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(N/A) binary operation $*$ on a set $S$ is a function $*: S \times S \rightarrow S$.
For the union operation $\cup: P \times P \rightarrow P$,for any two subsets $A, B \in P$,their union $A \cup B$ is also a subset of $X$,which means $A \cup B \in P$. Since every pair $(A, B)$ maps to a unique element $A \cup B$ in $P$,$\cup$ is a binary operation on $P$.
Similarly,for the intersection operation $\cap: P \times P \rightarrow P$,for any two subsets $A, B \in P$,their intersection $A \cap B$ is also a subset of $X$,which means $A \cap B \in P$. Since every pair $(A, B)$ maps to a unique element $A \cap B$ in $P$,$\cap$ is a binary operation on $P$.

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