Theorem rspc2vd 27129

Description: Deduction version of 2-variable restricted specialization, using implicit substitution. Notice that the class D for the second set variable y may depend on the first set variable x. (Contributed by AV, 29-Mar-2021.)

Hypotheses

Ref	Expression
rspc2vd.a	|- ( x = A -> ( th <-> ch ) )
rspc2vd.b	|- ( y = B -> ( ch <-> ps ) )
rspc2vd.c	|- ( ph -> A e. C )
rspc2vd.d	|- ( ( ph /\ x = A ) -> D = E )
rspc2vd.e	|- ( ph -> B e. E )

Assertion

Ref	Expression
rspc2vd	|- ( ph -> ( A. x e. C A. y e. D th -> ps ) )

Distinct variable groups:   x, A, y   y, B   x, C   y, D   x, E   ph, x   ch, x   ps, y

Allowed substitution hints:   ph( y)   ps( x)   ch( y)   th( x, y)   B( x)   C( y)   D( x)   E( y)

Proof of Theorem rspc2vd

Step	Hyp	Ref	Expression
1		rspc2vd.e	. . 3 |- ( ph -> B e. E )
2		rspc2vd.c	. . . 4 |- ( ph -> A e. C )
3		rspc2vd.d	. . . 4 |- ( ( ph /\ x = A ) -> D = E )
4	2, 3	csbied 3560	. . 3 |- ( ph -> [_ A / x ]_ D = E )
5	1, 4	eleqtrrd 2704	. 2 |- ( ph -> B e. [_ A / x ]_ D )
6		nfcsb1v 3549	. . . . 5 |- F/_ x [_ A / x ]_ D
7		nfv 1843	. . . . 5 |- F/ x ch
8	6, 7	nfral 2945	. . . 4 |- F/ x A. y e. [_ A / x ]_ D ch
9		csbeq1a 3542	. . . . 5 |- ( x = A -> D = [_ A / x ]_ D )
10		rspc2vd.a	. . . . 5 |- ( x = A -> ( th <-> ch ) )
11	9, 10	raleqbidv 3152	. . . 4 |- ( x = A -> ( A. y e. D th <-> A. y e. [_ A / x ]_ D ch ) )
12	8, 11	rspc 3303	. . 3 |- ( A e. C -> ( A. x e. C A. y e. D th -> A. y e. [_ A / x ]_ D ch ) )
13	2, 12	syl 17	. 2 |- ( ph -> ( A. x e. C A. y e. D th -> A. y e. [_ A / x ]_ D ch ) )
14		rspc2vd.b	. . 3 |- ( y = B -> ( ch <-> ps ) )
15	14	rspcv 3305	. 2 |- ( B e. [_ A / x ]_ D -> ( A. y e. [_ A / x ]_ D ch -> ps ) )
16	5, 13, 15	sylsyld 61	1 |- ( ph -> ( A. x e. C A. y e. D th -> ps ) )

Syntax hints:   -> wi 4   <-> wb 196   /\ wa 384   = wceq 1483   e. wcel 1990   A.wral 2912   [_csb 3533

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ral 2917  df-v 3202  df-sbc 3436  df-csb 3534

This theorem is referenced by:  frcond1  27130  frgrwopreglem4a  27174