Theorem rmob 3057

Description: Consequence of "at most one", using implicit substitution. (Contributed by NM, 2-Jan-2015.) (Revised by NM, 16-Jun-2017.)

Hypotheses

Ref	Expression
rmoi.b	|- ( x = B -> ( ph <-> ps ) )
rmoi.c	|- ( x = C -> ( ph <-> ch ) )

Assertion

Ref	Expression
rmob	|- ( ( E* x e. A ph /\ ( B e. A /\ ps ) ) -> ( B = C <-> ( C e. A /\ ch ) ) )

Distinct variable groups:   x, A   x, B   x, C   ps, x   ch, x

Allowed substitution hint:   ph( x)

Proof of Theorem rmob

Step	Hyp	Ref	Expression
1		df-rmo 2463	. 2 |- ( E* x e. A ph <-> E* x ( x e. A /\ ph ) )
2		simprl 529	. . . 4 |- ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> B e. A )
3		eleq1 2240	. . . 4 |- ( B = C -> ( B e. A <-> C e. A ) )
4	2, 3	syl5ibcom 155	. . 3 |- ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> ( B = C -> C e. A ) )
5		simpl 109	. . . 4 |- ( ( C e. A /\ ch ) -> C e. A )
6	5	a1i 9	. . 3 |- ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> ( ( C e. A /\ ch ) -> C e. A ) )
7		simplrl 535	. . . . 5 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> B e. A )
8		simpr 110	. . . . 5 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> C e. A )
9		simpll 527	. . . . 5 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> E* x ( x e. A /\ ph ) )
10		simplrr 536	. . . . 5 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> ps )
11		eleq1 2240	. . . . . . 7 |- ( x = B -> ( x e. A <-> B e. A ) )
12		rmoi.b	. . . . . . 7 |- ( x = B -> ( ph <-> ps ) )
13	11, 12	anbi12d 473	. . . . . 6 |- ( x = B -> ( ( x e. A /\ ph ) <-> ( B e. A /\ ps ) ) )
14		eleq1 2240	. . . . . . 7 |- ( x = C -> ( x e. A <-> C e. A ) )
15		rmoi.c	. . . . . . 7 |- ( x = C -> ( ph <-> ch ) )
16	14, 15	anbi12d 473	. . . . . 6 |- ( x = C -> ( ( x e. A /\ ph ) <-> ( C e. A /\ ch ) ) )
17	13, 16	mob 2921	. . . . 5 |- ( ( ( B e. A /\ C e. A ) /\ E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> ( B = C <-> ( C e. A /\ ch ) ) )
18	7, 8, 9, 7, 10, 17	syl212anc 1248	. . . 4 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> ( B = C <-> ( C e. A /\ ch ) ) )
19	18	ex 115	. . 3 |- ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> ( C e. A -> ( B = C <-> ( C e. A /\ ch ) ) ) )
20	4, 6, 19	pm5.21ndd 705	. 2 |- ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> ( B = C <-> ( C e. A /\ ch ) ) )
21	1, 20	sylanb 284	1 |- ( ( E* x e. A ph /\ ( B e. A /\ ps ) ) -> ( B = C <-> ( C e. A /\ ch ) ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1353   E*wmo 2027   e. wcel 2148   E*wrmo 2458

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-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-eu 2029  df-mo 2030  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-rmo 2463  df-v 2741

This theorem is referenced by:  rmoi  3058