Metamath Proof Explorer


Theorem rspec2

Description: Specialization rule for restricted quantification, with two quantifiers. (Contributed by NM, 20-Nov-1994)

Ref Expression
Hypothesis rspec2.1 xAyBφ
Assertion rspec2 xAyBφ

Proof

Step Hyp Ref Expression
1 rspec2.1 xAyBφ
2 1 rspec xAyBφ
3 2 r19.21bi xAyBφ