Metamath Proof Explorer


Theorem brralrspcev

Description: Restricted existential specialization with a restricted universal quantifier over a relation, closed form. (Contributed by AV, 20-Aug-2022)

Ref Expression
Assertion brralrspcev BXyYARBxXyYARx

Proof

Step Hyp Ref Expression
1 breq2 x=BARxARB
2 1 ralbidv x=ByYARxyYARB
3 2 rspcev BXyYARBxXyYARx