Metamath Proof Explorer


Theorem ceqsralt

Description: Restricted quantifier version of ceqsalt . (Contributed by NM, 28-Feb-2013) (Revised by Mario Carneiro, 10-Oct-2016)

Ref Expression
Assertion ceqsralt x ψ x x = A φ ψ A B x B x = A φ ψ

Proof

Step Hyp Ref Expression
1 biimt A B x x = A φ A B x x = A φ
2 df-ral x B x = A φ x x B x = A φ
3 eleq1 x = A x B A B
4 3 pm5.32ri x B x = A A B x = A
5 4 imbi1i x B x = A φ A B x = A φ
6 impexp x B x = A φ x B x = A φ
7 impexp A B x = A φ A B x = A φ
8 5 6 7 3bitr3i x B x = A φ A B x = A φ
9 8 albii x x B x = A φ x A B x = A φ
10 19.21v x A B x = A φ A B x x = A φ
11 2 9 10 3bitrri A B x x = A φ x B x = A φ
12 1 11 bitrdi A B x x = A φ x B x = A φ
13 12 3ad2ant3 x ψ x x = A φ ψ A B x x = A φ x B x = A φ
14 ceqsalt x ψ x x = A φ ψ A B x x = A φ ψ
15 13 14 bitr3d x ψ x x = A φ ψ A B x B x = A φ ψ