Theorem rmob 2850

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 2314	. 2 |- ( E* x e. A ph <-> E* x ( x e. A /\ ph ) )
2		simprl 483	. . . 4 |- ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> B e. A )
3		eleq1 2100	. . . 4 |- ( B = C -> ( B e. A <-> C e. A ) )
4	2, 3	syl5ibcom 144	. . 3 |- ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> ( B = C -> C e. A ) )
5		simpl 102	. . . 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 487	. . . . 5 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> B e. A )
8		simpr 103	. . . . 5 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> C e. A )
9		simpll 481	. . . . 5 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> E* x ( x e. A /\ ph ) )
10		simplrr 488	. . . . 5 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> ps )
11		eleq1 2100	. . . . . . 7 |- ( x = B -> ( x e. A <-> B e. A ) )
12		rmoi.b	. . . . . . 7 |- ( x = B -> ( ph <-> ps ) )
13	11, 12	anbi12d 442	. . . . . 6 |- ( x = B -> ( ( x e. A /\ ph ) <-> ( B e. A /\ ps ) ) )
14		eleq1 2100	. . . . . . 7 |- ( x = C -> ( x e. A <-> C e. A ) )
15		rmoi.c	. . . . . . 7 |- ( x = C -> ( ph <-> ch ) )
16	14, 15	anbi12d 442	. . . . . 6 |- ( x = C -> ( ( x e. A /\ ph ) <-> ( C e. A /\ ch ) ) )
17	13, 16	mob 2723	. . . . 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 1145	. . . 4 |- ( ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) /\ C e. A ) -> ( B = C <-> ( C e. A /\ ch ) ) )
19	18	ex 108	. . 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 621	. 2 |- ( ( E* x ( x e. A /\ ph ) /\ ( B e. A /\ ps ) ) -> ( B = C <-> ( C e. A /\ ch ) ) )
21	1, 20	sylanb 268	1 |- ( ( E* x e. A ph /\ ( B e. A /\ ps ) ) -> ( B = C <-> ( C e. A /\ ch ) ) )

Syntax hints:   -> wi 4   /\ wa 97   <-> wb 98   = wceq 1243   e. wcel 1393   E*wmo 1901   E*wrmo 2309

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022

This theorem depends on definitions:  df-bi 110  df-3an 887  df-tru 1246  df-nf 1350  df-sb 1646  df-eu 1903  df-mo 1904  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-rmo 2314  df-v 2559

This theorem is referenced by:  rmoi  2851