Metamath Proof Explorer


Theorem kmlem6

Description: Lemma for 5-quantifier AC of Kurt Maes, Th. 4, part of 4 => 1. (Contributed by NM, 26-Mar-2004)

Ref Expression
Assertion kmlem6 z x z z x w x φ A = z x v z w x φ ¬ v A

Proof

Step Hyp Ref Expression
1 r19.26 z x z w x φ A = z x z z x w x φ A =
2 n0 z v v z
3 2 biimpi z v v z
4 ne0i v A A
5 4 necon2bi A = ¬ v A
6 5 imim2i φ A = φ ¬ v A
7 6 ralimi w x φ A = w x φ ¬ v A
8 7 alrimiv w x φ A = v w x φ ¬ v A
9 19.29r v v z v w x φ ¬ v A v v z w x φ ¬ v A
10 df-rex v z w x φ ¬ v A v v z w x φ ¬ v A
11 9 10 sylibr v v z v w x φ ¬ v A v z w x φ ¬ v A
12 3 8 11 syl2an z w x φ A = v z w x φ ¬ v A
13 12 ralimi z x z w x φ A = z x v z w x φ ¬ v A
14 1 13 sylbir z x z z x w x φ A = z x v z w x φ ¬ v A