<Dl> <Dd> ⋂ A ∈ M A ⊆ ⋃ A ∈ M A . (\ displaystyle \ bigcap _ (A \ in M) A \ subseteq \ bigcup _ (A \ in M) A .) </Dd> </Dl> <Dd> ⋂ A ∈ M A ⊆ ⋃ A ∈ M A . (\ displaystyle \ bigcap _ (A \ in M) A \ subseteq \ bigcup _ (A \ in M) A .) </Dd> <P> Therefore, we can modify the definition slightly to </P> <Dl> <Dd> ⋂ A ∈ M A = (x ∈ ⋃ A ∈ M A: ∀ A ∈ M, x ∈ A). (\ displaystyle \ bigcap _ (A \ in M) A = \ left \ (x \ in \ bigcup _ (A \ in M) A: \ forall A \ in M, x \ in A \ right \).) </Dd> </Dl>

What elements may be found in the intersection of v and w