Metamath Proof Explorer


Theorem alrimi

Description: Inference form of Theorem 19.21 of Margaris p. 90, see 19.21 . (Contributed by Mario Carneiro, 24-Sep-2016)

Ref Expression
Hypotheses alrimi.1 xφ
alrimi.2 φψ
Assertion alrimi φxψ

Proof

Step Hyp Ref Expression
1 alrimi.1 xφ
2 alrimi.2 φψ
3 1 nf5ri φxφ
4 3 2 alrimih φxψ