Theorem rmob 3078

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 → (𝜑 ↔ 𝜓))
rmoi.c	⊢ (𝑥 = 𝐶 → (𝜑 ↔ 𝜒))

Assertion

Ref	Expression
rmob	⊢ ((∃*𝑥 ∈ 𝐴 𝜑 ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) → (𝐵 = 𝐶 ↔ (𝐶 ∈ 𝐴 ∧ 𝜒)))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵   𝑥,𝐶   𝜓,𝑥   𝜒,𝑥

Allowed substitution hint:   𝜑(𝑥)

Proof of Theorem rmob

Step	Hyp	Ref	Expression
1		df-rmo 2480	. 2 ⊢ (∃*𝑥 ∈ 𝐴 𝜑 ↔ ∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑))
2		simprl 529	. . . 4 ⊢ ((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) → 𝐵 ∈ 𝐴)
3		eleq1 2256	. . . 4 ⊢ (𝐵 = 𝐶 → (𝐵 ∈ 𝐴 ↔ 𝐶 ∈ 𝐴))
4	2, 3	syl5ibcom 155	. . 3 ⊢ ((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) → (𝐵 = 𝐶 → 𝐶 ∈ 𝐴))
5		simpl 109	. . . 4 ⊢ ((𝐶 ∈ 𝐴 ∧ 𝜒) → 𝐶 ∈ 𝐴)
6	5	a1i 9	. . 3 ⊢ ((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) → ((𝐶 ∈ 𝐴 ∧ 𝜒) → 𝐶 ∈ 𝐴))
7		simplrl 535	. . . . 5 ⊢ (((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) ∧ 𝐶 ∈ 𝐴) → 𝐵 ∈ 𝐴)
8		simpr 110	. . . . 5 ⊢ (((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) ∧ 𝐶 ∈ 𝐴) → 𝐶 ∈ 𝐴)
9		simpll 527	. . . . 5 ⊢ (((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) ∧ 𝐶 ∈ 𝐴) → ∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑))
10		simplrr 536	. . . . 5 ⊢ (((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) ∧ 𝐶 ∈ 𝐴) → 𝜓)
11		eleq1 2256	. . . . . . 7 ⊢ (𝑥 = 𝐵 → (𝑥 ∈ 𝐴 ↔ 𝐵 ∈ 𝐴))
12		rmoi.b	. . . . . . 7 ⊢ (𝑥 = 𝐵 → (𝜑 ↔ 𝜓))
13	11, 12	anbi12d 473	. . . . . 6 ⊢ (𝑥 = 𝐵 → ((𝑥 ∈ 𝐴 ∧ 𝜑) ↔ (𝐵 ∈ 𝐴 ∧ 𝜓)))
14		eleq1 2256	. . . . . . 7 ⊢ (𝑥 = 𝐶 → (𝑥 ∈ 𝐴 ↔ 𝐶 ∈ 𝐴))
15		rmoi.c	. . . . . . 7 ⊢ (𝑥 = 𝐶 → (𝜑 ↔ 𝜒))
16	14, 15	anbi12d 473	. . . . . 6 ⊢ (𝑥 = 𝐶 → ((𝑥 ∈ 𝐴 ∧ 𝜑) ↔ (𝐶 ∈ 𝐴 ∧ 𝜒)))
17	13, 16	mob 2942	. . . . 5 ⊢ (((𝐵 ∈ 𝐴 ∧ 𝐶 ∈ 𝐴) ∧ ∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) → (𝐵 = 𝐶 ↔ (𝐶 ∈ 𝐴 ∧ 𝜒)))
18	7, 8, 9, 7, 10, 17	syl212anc 1259	. . . 4 ⊢ (((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) ∧ 𝐶 ∈ 𝐴) → (𝐵 = 𝐶 ↔ (𝐶 ∈ 𝐴 ∧ 𝜒)))
19	18	ex 115	. . 3 ⊢ ((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) → (𝐶 ∈ 𝐴 → (𝐵 = 𝐶 ↔ (𝐶 ∈ 𝐴 ∧ 𝜒))))
20	4, 6, 19	pm5.21ndd 706	. 2 ⊢ ((∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) → (𝐵 = 𝐶 ↔ (𝐶 ∈ 𝐴 ∧ 𝜒)))
21	1, 20	sylanb 284	1 ⊢ ((∃*𝑥 ∈ 𝐴 𝜑 ∧ (𝐵 ∈ 𝐴 ∧ 𝜓)) → (𝐵 = 𝐶 ↔ (𝐶 ∈ 𝐴 ∧ 𝜒)))

Syntax hints:   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1364  ∃*wmo 2043   ∈ wcel 2164  ∃*wrmo 2475

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 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2175

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1472  df-sb 1774  df-eu 2045  df-mo 2046  df-clab 2180  df-cleq 2186  df-clel 2189  df-nfc 2325  df-rmo 2480  df-v 2762

This theorem is referenced by:  rmoi  3079