Theorem reusv3i 4458

Description: Two ways of expressing existential uniqueness via an indirect equality. (Contributed by NM, 23-Dec-2012.)

Hypotheses

Ref	Expression
reusv3.1	|- ( y = z -> ( ph <-> ps ) )
reusv3.2	|- ( y = z -> C = D )

Assertion

Ref	Expression
reusv3i	|- ( E. x e. A A. y e. B ( ph -> x = C ) -> A. y e. B A. z e. B ( ( ph /\ ps ) -> C = D ) )

Distinct variable groups:   x, y, z, B   x, C, z   x, D, y   ph, x, z   ps, x, y

Allowed substitution hints:   ph( y)   ps( z)   A( x, y, z)   C( y)   D( z)

Proof of Theorem reusv3i

Step	Hyp	Ref	Expression
1		reusv3.1	. . . . . 6 |- ( y = z -> ( ph <-> ps ) )
2		reusv3.2	. . . . . . 7 |- ( y = z -> C = D )
3	2	eqeq2d 2189	. . . . . 6 |- ( y = z -> ( x = C <-> x = D ) )
4	1, 3	imbi12d 234	. . . . 5 |- ( y = z -> ( ( ph -> x = C ) <-> ( ps -> x = D ) ) )
5	4	cbvralv 2703	. . . 4 |- ( A. y e. B ( ph -> x = C ) <-> A. z e. B ( ps -> x = D ) )
6	5	biimpi 120	. . 3 |- ( A. y e. B ( ph -> x = C ) -> A. z e. B ( ps -> x = D ) )
7		raaanv 3530	. . . 4 |- ( A. y e. B A. z e. B ( ( ph -> x = C ) /\ ( ps -> x = D ) ) <-> ( A. y e. B ( ph -> x = C ) /\ A. z e. B ( ps -> x = D ) ) )
8		anim12 344	. . . . . . 7 |- ( ( ( ph -> x = C ) /\ ( ps -> x = D ) ) -> ( ( ph /\ ps ) -> ( x = C /\ x = D ) ) )
9		eqtr2 2196	. . . . . . 7 |- ( ( x = C /\ x = D ) -> C = D )
10	8, 9	syl6 33	. . . . . 6 |- ( ( ( ph -> x = C ) /\ ( ps -> x = D ) ) -> ( ( ph /\ ps ) -> C = D ) )
11	10	ralimi 2540	. . . . 5 |- ( A. z e. B ( ( ph -> x = C ) /\ ( ps -> x = D ) ) -> A. z e. B ( ( ph /\ ps ) -> C = D ) )
12	11	ralimi 2540	. . . 4 |- ( A. y e. B A. z e. B ( ( ph -> x = C ) /\ ( ps -> x = D ) ) -> A. y e. B A. z e. B ( ( ph /\ ps ) -> C = D ) )
13	7, 12	sylbir 135	. . 3 |- ( ( A. y e. B ( ph -> x = C ) /\ A. z e. B ( ps -> x = D ) ) -> A. y e. B A. z e. B ( ( ph /\ ps ) -> C = D ) )
14	6, 13	mpdan 421	. 2 |- ( A. y e. B ( ph -> x = C ) -> A. y e. B A. z e. B ( ( ph /\ ps ) -> C = D ) )
15	14	rexlimivw 2590	1 |- ( E. x e. A A. y e. B ( ph -> x = C ) -> A. y e. B A. z e. B ( ( ph /\ ps ) -> C = D ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1353   A.wral 2455   E.wrex 2456

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159

This theorem depends on definitions:  df-bi 117  df-tru 1356  df-nf 1461  df-sb 1763  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ral 2460  df-rex 2461

This theorem is referenced by:  reusv3  4459