What is the difference between
$\forall x,\exists y, ((x,y) \in A \implies x \in B)$
and
$\forall x,((\exists y, (x,y) \in A) \implies x \in B)$ ?
I understand that the second means that $pr_1 A \subseteq B$, but what about the first sentence ?
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Sign up to join this communityWhat is the difference between
$\forall x,\exists y, ((x,y) \in A \implies x \in B)$
and
$\forall x,((\exists y, (x,y) \in A) \implies x \in B)$ ?
I understand that the second means that $pr_1 A \subseteq B$, but what about the first sentence ?
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