Theorem riotass2 6057

Description: Restriction of a unique element to a smaller class. (Contributed by NM, 21-Aug-2011.) (Revised by NM, 22-Mar-2013.)

Assertion

Ref	Expression
riotass2	⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑥 ∈ 𝐵 𝜓))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑥)

Proof of Theorem riotass2

Step	Hyp	Ref	Expression
1		reuss2 3513	. . . 4 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → ∃!𝑥 ∈ 𝐴 𝜑)
2		simplr 533	. . . 4 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓))
3		riotasbc 6045	. . . . 5 ⊢ (∃!𝑥 ∈ 𝐴 𝜑 → [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜑)
4		riotacl 6044	. . . . . 6 ⊢ (∃!𝑥 ∈ 𝐴 𝜑 → (℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴)
5		rspsbc 3135	. . . . . . 7 ⊢ ((℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴 → (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥](𝜑 → 𝜓)))
6		sbcimg 3093	. . . . . . 7 ⊢ ((℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴 → ([(℩𝑥 ∈ 𝐴 𝜑) / 𝑥](𝜑 → 𝜓) ↔ ([(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜑 → [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓)))
7	5, 6	sylibd 149	. . . . . 6 ⊢ ((℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴 → (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → ([(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜑 → [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓)))
8	4, 7	syl 14	. . . . 5 ⊢ (∃!𝑥 ∈ 𝐴 𝜑 → (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → ([(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜑 → [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓)))
9	3, 8	mpid 42	. . . 4 ⊢ (∃!𝑥 ∈ 𝐴 𝜑 → (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓))
10	1, 2, 9	sylc 62	. . 3 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓)
11	1, 4	syl 14	. . . . 5 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → (℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴)
12		ssel 3242	. . . . . 6 ⊢ (𝐴 ⊆ 𝐵 → ((℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴 → (℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐵))
13	12	ad2antrr 492	. . . . 5 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → ((℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴 → (℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐵))
14	11, 13	mpd 13	. . . 4 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → (℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐵)
15		simprr 537	. . . 4 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → ∃!𝑥 ∈ 𝐵 𝜓)
16		nfriota1 6036	. . . . 5 ⊢ Ⅎ𝑥(℩𝑥 ∈ 𝐴 𝜑)
17	16	nfsbc1 3069	. . . . 5 ⊢ Ⅎ𝑥[(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓
18		sbceq1a 3061	. . . . 5 ⊢ (𝑥 = (℩𝑥 ∈ 𝐴 𝜑) → (𝜓 ↔ [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓))
19	16, 17, 18	riota2f 6051	. . . 4 ⊢ (((℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐵 ∧ ∃!𝑥 ∈ 𝐵 𝜓) → ([(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓 ↔ (℩𝑥 ∈ 𝐵 𝜓) = (℩𝑥 ∈ 𝐴 𝜑)))
20	14, 15, 19	syl2anc 415	. . 3 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → ([(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜓 ↔ (℩𝑥 ∈ 𝐵 𝜓) = (℩𝑥 ∈ 𝐴 𝜑)))
21	10, 20	mpbid 147	. 2 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → (℩𝑥 ∈ 𝐵 𝜓) = (℩𝑥 ∈ 𝐴 𝜑))
22	21	eqcomd 2244	1 ⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑥 ∈ 𝐵 𝜓))

Syntax hints:   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1402   ∈ wcel 2209  ∀wral 2528  ∃wrex 2529  ∃!wreu 2530  [wsbc 3051   ⊆ wss 3220  ℩crio 6027

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 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220

This theorem depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-un 3224  df-in 3226  df-ss 3233  df-sn 3711  df-pr 3712  df-uni 3931  df-iota 5332  df-riota 6028

This theorem is referenced by: (None)