Theorem dfac5lem3 9739

Description: Lemma for dfac5 9742. (Contributed by NM, 12-Apr-2004.)

Hypothesis

Ref	Expression
dfac5lem.1	⊢ 𝐴 = {𝑢 ∣ (𝑢 ≠ ∅ ∧ ∃𝑡 ∈ ℎ 𝑢 = ({𝑡} × 𝑡))}

Assertion

Ref	Expression
dfac5lem3	⊢ (({𝑤} × 𝑤) ∈ 𝐴 ↔ (𝑤 ≠ ∅ ∧ 𝑤 ∈ ℎ))

Distinct variable groups:   𝑤,𝑢,𝑡,ℎ   𝑤,𝐴

Allowed substitution hints:   𝐴(𝑢,𝑡,ℎ)

Proof of Theorem dfac5lem3

Step	Hyp	Ref	Expression
1		snex 5324	. . . 4 ⊢ {𝑤} ∈ V
2		vex 3412	. . . 4 ⊢ 𝑤 ∈ V
3	1, 2	xpex 7538	. . 3 ⊢ ({𝑤} × 𝑤) ∈ V
4		neeq1 3003	. . . 4 ⊢ (𝑢 = ({𝑤} × 𝑤) → (𝑢 ≠ ∅ ↔ ({𝑤} × 𝑤) ≠ ∅))
5		eqeq1 2741	. . . . 5 ⊢ (𝑢 = ({𝑤} × 𝑤) → (𝑢 = ({𝑡} × 𝑡) ↔ ({𝑤} × 𝑤) = ({𝑡} × 𝑡)))
6	5	rexbidv 3216	. . . 4 ⊢ (𝑢 = ({𝑤} × 𝑤) → (∃𝑡 ∈ ℎ 𝑢 = ({𝑡} × 𝑡) ↔ ∃𝑡 ∈ ℎ ({𝑤} × 𝑤) = ({𝑡} × 𝑡)))
7	4, 6	anbi12d 634	. . 3 ⊢ (𝑢 = ({𝑤} × 𝑤) → ((𝑢 ≠ ∅ ∧ ∃𝑡 ∈ ℎ 𝑢 = ({𝑡} × 𝑡)) ↔ (({𝑤} × 𝑤) ≠ ∅ ∧ ∃𝑡 ∈ ℎ ({𝑤} × 𝑤) = ({𝑡} × 𝑡))))
8	3, 7	elab 3587	. 2 ⊢ (({𝑤} × 𝑤) ∈ {𝑢 ∣ (𝑢 ≠ ∅ ∧ ∃𝑡 ∈ ℎ 𝑢 = ({𝑡} × 𝑡))} ↔ (({𝑤} × 𝑤) ≠ ∅ ∧ ∃𝑡 ∈ ℎ ({𝑤} × 𝑤) = ({𝑡} × 𝑡)))
9		dfac5lem.1	. . 3 ⊢ 𝐴 = {𝑢 ∣ (𝑢 ≠ ∅ ∧ ∃𝑡 ∈ ℎ 𝑢 = ({𝑡} × 𝑡))}
10	9	eleq2i 2829	. 2 ⊢ (({𝑤} × 𝑤) ∈ 𝐴 ↔ ({𝑤} × 𝑤) ∈ {𝑢 ∣ (𝑢 ≠ ∅ ∧ ∃𝑡 ∈ ℎ 𝑢 = ({𝑡} × 𝑡))})
11		xpeq2 5572	. . . . . 6 ⊢ (𝑤 = ∅ → ({𝑤} × 𝑤) = ({𝑤} × ∅))
12		xp0 6021	. . . . . 6 ⊢ ({𝑤} × ∅) = ∅
13	11, 12	eqtrdi 2794	. . . . 5 ⊢ (𝑤 = ∅ → ({𝑤} × 𝑤) = ∅)
14		rneq 5805	. . . . . 6 ⊢ (({𝑤} × 𝑤) = ∅ → ran ({𝑤} × 𝑤) = ran ∅)
15	2	snnz 4692	. . . . . . 7 ⊢ {𝑤} ≠ ∅
16		rnxp 6033	. . . . . . 7 ⊢ ({𝑤} ≠ ∅ → ran ({𝑤} × 𝑤) = 𝑤)
17	15, 16	ax-mp 5	. . . . . 6 ⊢ ran ({𝑤} × 𝑤) = 𝑤
18		rn0 5795	. . . . . 6 ⊢ ran ∅ = ∅
19	14, 17, 18	3eqtr3g 2801	. . . . 5 ⊢ (({𝑤} × 𝑤) = ∅ → 𝑤 = ∅)
20	13, 19	impbii 212	. . . 4 ⊢ (𝑤 = ∅ ↔ ({𝑤} × 𝑤) = ∅)
21	20	necon3bii 2993	. . 3 ⊢ (𝑤 ≠ ∅ ↔ ({𝑤} × 𝑤) ≠ ∅)
22		df-rex 3067	. . . 4 ⊢ (∃𝑡 ∈ ℎ ({𝑤} × 𝑤) = ({𝑡} × 𝑡) ↔ ∃𝑡(𝑡 ∈ ℎ ∧ ({𝑤} × 𝑤) = ({𝑡} × 𝑡)))
23		rneq 5805	. . . . . . . . 9 ⊢ (({𝑤} × 𝑤) = ({𝑡} × 𝑡) → ran ({𝑤} × 𝑤) = ran ({𝑡} × 𝑡))
24		vex 3412	. . . . . . . . . . 11 ⊢ 𝑡 ∈ V
25	24	snnz 4692	. . . . . . . . . 10 ⊢ {𝑡} ≠ ∅
26		rnxp 6033	. . . . . . . . . 10 ⊢ ({𝑡} ≠ ∅ → ran ({𝑡} × 𝑡) = 𝑡)
27	25, 26	ax-mp 5	. . . . . . . . 9 ⊢ ran ({𝑡} × 𝑡) = 𝑡
28	23, 17, 27	3eqtr3g 2801	. . . . . . . 8 ⊢ (({𝑤} × 𝑤) = ({𝑡} × 𝑡) → 𝑤 = 𝑡)
29		sneq 4551	. . . . . . . . . 10 ⊢ (𝑤 = 𝑡 → {𝑤} = {𝑡})
30	29	xpeq1d 5580	. . . . . . . . 9 ⊢ (𝑤 = 𝑡 → ({𝑤} × 𝑤) = ({𝑡} × 𝑤))
31		xpeq2 5572	. . . . . . . . 9 ⊢ (𝑤 = 𝑡 → ({𝑡} × 𝑤) = ({𝑡} × 𝑡))
32	30, 31	eqtrd 2777	. . . . . . . 8 ⊢ (𝑤 = 𝑡 → ({𝑤} × 𝑤) = ({𝑡} × 𝑡))
33	28, 32	impbii 212	. . . . . . 7 ⊢ (({𝑤} × 𝑤) = ({𝑡} × 𝑡) ↔ 𝑤 = 𝑡)
34		equcom 2026	. . . . . . 7 ⊢ (𝑤 = 𝑡 ↔ 𝑡 = 𝑤)
35	33, 34	bitri 278	. . . . . 6 ⊢ (({𝑤} × 𝑤) = ({𝑡} × 𝑡) ↔ 𝑡 = 𝑤)
36	35	anbi1ci 629	. . . . 5 ⊢ ((𝑡 ∈ ℎ ∧ ({𝑤} × 𝑤) = ({𝑡} × 𝑡)) ↔ (𝑡 = 𝑤 ∧ 𝑡 ∈ ℎ))
37	36	exbii 1855	. . . 4 ⊢ (∃𝑡(𝑡 ∈ ℎ ∧ ({𝑤} × 𝑤) = ({𝑡} × 𝑡)) ↔ ∃𝑡(𝑡 = 𝑤 ∧ 𝑡 ∈ ℎ))
38		elequ1 2117	. . . . 5 ⊢ (𝑡 = 𝑤 → (𝑡 ∈ ℎ ↔ 𝑤 ∈ ℎ))
39	38	equsexvw 2013	. . . 4 ⊢ (∃𝑡(𝑡 = 𝑤 ∧ 𝑡 ∈ ℎ) ↔ 𝑤 ∈ ℎ)
40	22, 37, 39	3bitrri 301	. . 3 ⊢ (𝑤 ∈ ℎ ↔ ∃𝑡 ∈ ℎ ({𝑤} × 𝑤) = ({𝑡} × 𝑡))
41	21, 40	anbi12i 630	. 2 ⊢ ((𝑤 ≠ ∅ ∧ 𝑤 ∈ ℎ) ↔ (({𝑤} × 𝑤) ≠ ∅ ∧ ∃𝑡 ∈ ℎ ({𝑤} × 𝑤) = ({𝑡} × 𝑡)))
42	8, 10, 41	3bitr4i 306	1 ⊢ (({𝑤} × 𝑤) ∈ 𝐴 ↔ (𝑤 ≠ ∅ ∧ 𝑤 ∈ ℎ))

Syntax hints:   ↔ wb 209   ∧ wa 399   = wceq 1543  ∃wex 1787   ∈ wcel 2110  {cab 2714   ≠ wne 2940  ∃wrex 3062  ∅c0 4237  {csn 4541   × cxp 5549  ran crn 5552

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1803  ax-4 1817  ax-5 1918  ax-6 1976  ax-7 2016  ax-8 2112  ax-9 2120  ax-10 2141  ax-11 2158  ax-12 2175  ax-ext 2708  ax-sep 5192  ax-nul 5199  ax-pow 5258  ax-pr 5322  ax-un 7523

This theorem depends on definitions:  df-bi 210  df-an 400  df-or 848  df-3an 1091  df-tru 1546  df-fal 1556  df-ex 1788  df-nf 1792  df-sb 2071  df-mo 2539  df-eu 2568  df-clab 2715  df-cleq 2729  df-clel 2816  df-nfc 2886  df-ne 2941  df-ral 3066  df-rex 3067  df-rab 3070  df-v 3410  df-dif 3869  df-un 3871  df-in 3873  df-ss 3883  df-nul 4238  df-if 4440  df-pw 4515  df-sn 4542  df-pr 4544  df-op 4548  df-uni 4820  df-br 5054  df-opab 5116  df-xp 5557  df-rel 5558  df-cnv 5559  df-dm 5561  df-rn 5562

This theorem is referenced by:  dfac5lem5  9741