Suppose $A \subseteq C$ and $B$ and $C$ are disjoint. Prove that $x \in A \rightarrow x \notin B$.
Basically I need to prove this.
Suppose $A \subseteq C$ and $B$ and $C$ are disjoint. Prove that $x \in A \rightarrow x \notin B$.
Basically I need to prove this.