Theorem unxpwdom2 8493

Description: Lemma for unxpwdom 8494. (Contributed by Mario Carneiro, 15-May-2015.)

Assertion

Ref	Expression
unxpwdom2	⊢ ((𝐴 × 𝐴) ≈ (𝐵 ∪ 𝐶) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶))

Proof of Theorem unxpwdom2

Dummy variables 𝑥 𝑓 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		ensym 8005	. 2 ⊢ ((𝐴 × 𝐴) ≈ (𝐵 ∪ 𝐶) → (𝐵 ∪ 𝐶) ≈ (𝐴 × 𝐴))
2		bren 7964	. . 3 ⊢ ((𝐵 ∪ 𝐶) ≈ (𝐴 × 𝐴) ↔ ∃𝑓 𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴))
3		ssdif0 3942	. . . . . 6 ⊢ (𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ↔ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) = ∅)
4		dmxpid 5345	. . . . . . . . . . . . . 14 ⊢ dom (𝐴 × 𝐴) = 𝐴
5		f1ofo 6144	. . . . . . . . . . . . . . . . 17 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → 𝑓:(𝐵 ∪ 𝐶)–onto→(𝐴 × 𝐴))
6		forn 6118	. . . . . . . . . . . . . . . . 17 ⊢ (𝑓:(𝐵 ∪ 𝐶)–onto→(𝐴 × 𝐴) → ran 𝑓 = (𝐴 × 𝐴))
7	5, 6	syl 17	. . . . . . . . . . . . . . . 16 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → ran 𝑓 = (𝐴 × 𝐴))
8		vex 3203	. . . . . . . . . . . . . . . . 17 ⊢ 𝑓 ∈ V
9	8	rnex 7100	. . . . . . . . . . . . . . . 16 ⊢ ran 𝑓 ∈ V
10	7, 9	syl6eqelr 2710	. . . . . . . . . . . . . . 15 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (𝐴 × 𝐴) ∈ V)
11		dmexg 7097	. . . . . . . . . . . . . . 15 ⊢ ((𝐴 × 𝐴) ∈ V → dom (𝐴 × 𝐴) ∈ V)
12	10, 11	syl 17	. . . . . . . . . . . . . 14 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → dom (𝐴 × 𝐴) ∈ V)
13	4, 12	syl5eqelr 2706	. . . . . . . . . . . . 13 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → 𝐴 ∈ V)
14		imassrn 5477	. . . . . . . . . . . . . 14 ⊢ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ⊆ ran ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓)
15		f1stres 7190	. . . . . . . . . . . . . . . 16 ⊢ (1st ↾ (𝐴 × 𝐴)):(𝐴 × 𝐴)⟶𝐴
16		f1of 6137	. . . . . . . . . . . . . . . 16 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → 𝑓:(𝐵 ∪ 𝐶)⟶(𝐴 × 𝐴))
17		fco 6058	. . . . . . . . . . . . . . . 16 ⊢ (((1st ↾ (𝐴 × 𝐴)):(𝐴 × 𝐴)⟶𝐴 ∧ 𝑓:(𝐵 ∪ 𝐶)⟶(𝐴 × 𝐴)) → ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓):(𝐵 ∪ 𝐶)⟶𝐴)
18	15, 16, 17	sylancr 695	. . . . . . . . . . . . . . 15 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓):(𝐵 ∪ 𝐶)⟶𝐴)
19		frn 6053	. . . . . . . . . . . . . . 15 ⊢ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓):(𝐵 ∪ 𝐶)⟶𝐴 → ran ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) ⊆ 𝐴)
20	18, 19	syl 17	. . . . . . . . . . . . . 14 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → ran ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) ⊆ 𝐴)
21	14, 20	syl5ss 3614	. . . . . . . . . . . . 13 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ⊆ 𝐴)
22	13, 21	ssexd 4805	. . . . . . . . . . . 12 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ∈ V)
23	22	adantr 481	. . . . . . . . . . 11 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ∈ V)
24		simpr 477	. . . . . . . . . . 11 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → 𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
25		ssdomg 8001	. . . . . . . . . . 11 ⊢ ((((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ∈ V → (𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) → 𝐴 ≼ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)))
26	23, 24, 25	sylc 65	. . . . . . . . . 10 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → 𝐴 ≼ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
27		domwdom 8479	. . . . . . . . . 10 ⊢ (𝐴 ≼ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) → 𝐴 ≼* (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
28	26, 27	syl 17	. . . . . . . . 9 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → 𝐴 ≼* (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
29		ffun 6048	. . . . . . . . . . . 12 ⊢ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓):(𝐵 ∪ 𝐶)⟶𝐴 → Fun ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓))
30	18, 29	syl 17	. . . . . . . . . . 11 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → Fun ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓))
31		ssun1 3776	. . . . . . . . . . . 12 ⊢ 𝐵 ⊆ (𝐵 ∪ 𝐶)
32		f1odm 6141	. . . . . . . . . . . . 13 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → dom 𝑓 = (𝐵 ∪ 𝐶))
33	8	dmex 7099	. . . . . . . . . . . . 13 ⊢ dom 𝑓 ∈ V
34	32, 33	syl6eqelr 2710	. . . . . . . . . . . 12 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (𝐵 ∪ 𝐶) ∈ V)
35		ssexg 4804	. . . . . . . . . . . 12 ⊢ ((𝐵 ⊆ (𝐵 ∪ 𝐶) ∧ (𝐵 ∪ 𝐶) ∈ V) → 𝐵 ∈ V)
36	31, 34, 35	sylancr 695	. . . . . . . . . . 11 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → 𝐵 ∈ V)
37		wdomima2g 8491	. . . . . . . . . . 11 ⊢ ((Fun ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) ∧ 𝐵 ∈ V ∧ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ∈ V) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ≼* 𝐵)
38	30, 36, 22, 37	syl3anc 1326	. . . . . . . . . 10 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ≼* 𝐵)
39	38	adantr 481	. . . . . . . . 9 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ≼* 𝐵)
40		wdomtr 8480	. . . . . . . . 9 ⊢ ((𝐴 ≼* (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ∧ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) ≼* 𝐵) → 𝐴 ≼* 𝐵)
41	28, 39, 40	syl2anc 693	. . . . . . . 8 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → 𝐴 ≼* 𝐵)
42	41	orcd 407	. . . . . . 7 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶))
43	42	ex 450	. . . . . 6 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (𝐴 ⊆ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶)))
44	3, 43	syl5bir 233	. . . . 5 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → ((𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) = ∅ → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶)))
45		n0 3931	. . . . . 6 ⊢ ((𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) ≠ ∅ ↔ ∃𝑥 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)))
46		ssun2 3777	. . . . . . . . . . . . 13 ⊢ 𝐶 ⊆ (𝐵 ∪ 𝐶)
47		ssexg 4804	. . . . . . . . . . . . 13 ⊢ ((𝐶 ⊆ (𝐵 ∪ 𝐶) ∧ (𝐵 ∪ 𝐶) ∈ V) → 𝐶 ∈ V)
48	46, 34, 47	sylancr 695	. . . . . . . . . . . 12 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → 𝐶 ∈ V)
49	48	adantr 481	. . . . . . . . . . 11 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → 𝐶 ∈ V)
50		f1ofn 6138	. . . . . . . . . . . . . . 15 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → 𝑓 Fn (𝐵 ∪ 𝐶))
51		elpreima 6337	. . . . . . . . . . . . . . 15 ⊢ (𝑓 Fn (𝐵 ∪ 𝐶) → (𝑦 ∈ (◡𝑓 “ ({𝑥} × 𝐴)) ↔ (𝑦 ∈ (𝐵 ∪ 𝐶) ∧ (𝑓‘𝑦) ∈ ({𝑥} × 𝐴))))
52	50, 51	syl 17	. . . . . . . . . . . . . 14 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (𝑦 ∈ (◡𝑓 “ ({𝑥} × 𝐴)) ↔ (𝑦 ∈ (𝐵 ∪ 𝐶) ∧ (𝑓‘𝑦) ∈ ({𝑥} × 𝐴))))
53	52	adantr 481	. . . . . . . . . . . . 13 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (𝑦 ∈ (◡𝑓 “ ({𝑥} × 𝐴)) ↔ (𝑦 ∈ (𝐵 ∪ 𝐶) ∧ (𝑓‘𝑦) ∈ ({𝑥} × 𝐴))))
54		elun 3753	. . . . . . . . . . . . . . . 16 ⊢ (𝑦 ∈ (𝐵 ∪ 𝐶) ↔ (𝑦 ∈ 𝐵 ∨ 𝑦 ∈ 𝐶))
55		df-or 385	. . . . . . . . . . . . . . . 16 ⊢ ((𝑦 ∈ 𝐵 ∨ 𝑦 ∈ 𝐶) ↔ (¬ 𝑦 ∈ 𝐵 → 𝑦 ∈ 𝐶))
56	54, 55	bitri 264	. . . . . . . . . . . . . . 15 ⊢ (𝑦 ∈ (𝐵 ∪ 𝐶) ↔ (¬ 𝑦 ∈ 𝐵 → 𝑦 ∈ 𝐶))
57		eldifn 3733	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → ¬ 𝑥 ∈ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
58	57	ad2antlr 763	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ (𝑓‘𝑦) ∈ ({𝑥} × 𝐴)) → ¬ 𝑥 ∈ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
59	16	ad2antrr 762	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → 𝑓:(𝐵 ∪ 𝐶)⟶(𝐴 × 𝐴))
60		simprr 796	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → 𝑦 ∈ 𝐵)
61	31, 60	sseldi 3601	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → 𝑦 ∈ (𝐵 ∪ 𝐶))
62		fvco3 6275	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((𝑓:(𝐵 ∪ 𝐶)⟶(𝐴 × 𝐴) ∧ 𝑦 ∈ (𝐵 ∪ 𝐶)) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓)‘𝑦) = ((1st ↾ (𝐴 × 𝐴))‘(𝑓‘𝑦)))
63	59, 61, 62	syl2anc 693	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓)‘𝑦) = ((1st ↾ (𝐴 × 𝐴))‘(𝑓‘𝑦)))
64		eldifi 3732	. . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 ⊢ (𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → 𝑥 ∈ 𝐴)
65	64	adantl 482	. . . . . . . . . . . . . . . . . . . . . . . . . . . 28 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → 𝑥 ∈ 𝐴)
66	65	snssd 4340	. . . . . . . . . . . . . . . . . . . . . . . . . . 27 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → {𝑥} ⊆ 𝐴)
67		xpss1 5228	. . . . . . . . . . . . . . . . . . . . . . . . . . 27 ⊢ ({𝑥} ⊆ 𝐴 → ({𝑥} × 𝐴) ⊆ (𝐴 × 𝐴))
68	66, 67	syl 17	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → ({𝑥} × 𝐴) ⊆ (𝐴 × 𝐴))
69	68	adantr 481	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → ({𝑥} × 𝐴) ⊆ (𝐴 × 𝐴))
70		simprl 794	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → (𝑓‘𝑦) ∈ ({𝑥} × 𝐴))
71	69, 70	sseldd 3604	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → (𝑓‘𝑦) ∈ (𝐴 × 𝐴))
72		fvres 6207	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ ((𝑓‘𝑦) ∈ (𝐴 × 𝐴) → ((1st ↾ (𝐴 × 𝐴))‘(𝑓‘𝑦)) = (1st ‘(𝑓‘𝑦)))
73	71, 72	syl 17	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → ((1st ↾ (𝐴 × 𝐴))‘(𝑓‘𝑦)) = (1st ‘(𝑓‘𝑦)))
74		xp1st 7198	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) → (1st ‘(𝑓‘𝑦)) ∈ {𝑥})
75	70, 74	syl 17	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → (1st ‘(𝑓‘𝑦)) ∈ {𝑥})
76	73, 75	eqeltrd 2701	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → ((1st ↾ (𝐴 × 𝐴))‘(𝑓‘𝑦)) ∈ {𝑥})
77		elsni 4194	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (((1st ↾ (𝐴 × 𝐴))‘(𝑓‘𝑦)) ∈ {𝑥} → ((1st ↾ (𝐴 × 𝐴))‘(𝑓‘𝑦)) = 𝑥)
78	76, 77	syl 17	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → ((1st ↾ (𝐴 × 𝐴))‘(𝑓‘𝑦)) = 𝑥)
79	63, 78	eqtrd 2656	. . . . . . . . . . . . . . . . . . . 20 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓)‘𝑦) = 𝑥)
80		ffn 6045	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓):(𝐵 ∪ 𝐶)⟶𝐴 → ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) Fn (𝐵 ∪ 𝐶))
81	18, 80	syl 17	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) Fn (𝐵 ∪ 𝐶))
82	81	ad2antrr 762	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → ((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) Fn (𝐵 ∪ 𝐶))
83	31	a1i 11	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → 𝐵 ⊆ (𝐵 ∪ 𝐶))
84		fnfvima 6496	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) Fn (𝐵 ∪ 𝐶) ∧ 𝐵 ⊆ (𝐵 ∪ 𝐶) ∧ 𝑦 ∈ 𝐵) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓)‘𝑦) ∈ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
85	82, 83, 60, 84	syl3anc 1326	. . . . . . . . . . . . . . . . . . . 20 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓)‘𝑦) ∈ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
86	79, 85	eqeltrrd 2702	. . . . . . . . . . . . . . . . . . 19 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) ∧ 𝑦 ∈ 𝐵)) → 𝑥 ∈ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))
87	86	expr 643	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ (𝑓‘𝑦) ∈ ({𝑥} × 𝐴)) → (𝑦 ∈ 𝐵 → 𝑥 ∈ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)))
88	58, 87	mtod 189	. . . . . . . . . . . . . . . . 17 ⊢ (((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) ∧ (𝑓‘𝑦) ∈ ({𝑥} × 𝐴)) → ¬ 𝑦 ∈ 𝐵)
89	88	ex 450	. . . . . . . . . . . . . . . 16 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) → ¬ 𝑦 ∈ 𝐵))
90	89	imim1d 82	. . . . . . . . . . . . . . 15 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → ((¬ 𝑦 ∈ 𝐵 → 𝑦 ∈ 𝐶) → ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) → 𝑦 ∈ 𝐶)))
91	56, 90	syl5bi 232	. . . . . . . . . . . . . 14 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (𝑦 ∈ (𝐵 ∪ 𝐶) → ((𝑓‘𝑦) ∈ ({𝑥} × 𝐴) → 𝑦 ∈ 𝐶)))
92	91	impd 447	. . . . . . . . . . . . 13 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → ((𝑦 ∈ (𝐵 ∪ 𝐶) ∧ (𝑓‘𝑦) ∈ ({𝑥} × 𝐴)) → 𝑦 ∈ 𝐶))
93	53, 92	sylbid 230	. . . . . . . . . . . 12 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (𝑦 ∈ (◡𝑓 “ ({𝑥} × 𝐴)) → 𝑦 ∈ 𝐶))
94	93	ssrdv 3609	. . . . . . . . . . 11 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (◡𝑓 “ ({𝑥} × 𝐴)) ⊆ 𝐶)
95		ssdomg 8001	. . . . . . . . . . 11 ⊢ (𝐶 ∈ V → ((◡𝑓 “ ({𝑥} × 𝐴)) ⊆ 𝐶 → (◡𝑓 “ ({𝑥} × 𝐴)) ≼ 𝐶))
96	49, 94, 95	sylc 65	. . . . . . . . . 10 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (◡𝑓 “ ({𝑥} × 𝐴)) ≼ 𝐶)
97		f1ocnv 6149	. . . . . . . . . . . . . . 15 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → ◡𝑓:(𝐴 × 𝐴)–1-1-onto→(𝐵 ∪ 𝐶))
98		f1of1 6136	. . . . . . . . . . . . . . 15 ⊢ (◡𝑓:(𝐴 × 𝐴)–1-1-onto→(𝐵 ∪ 𝐶) → ◡𝑓:(𝐴 × 𝐴)–1-1→(𝐵 ∪ 𝐶))
99	97, 98	syl 17	. . . . . . . . . . . . . 14 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → ◡𝑓:(𝐴 × 𝐴)–1-1→(𝐵 ∪ 𝐶))
100	99	adantr 481	. . . . . . . . . . . . 13 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → ◡𝑓:(𝐴 × 𝐴)–1-1→(𝐵 ∪ 𝐶))
101	34	adantr 481	. . . . . . . . . . . . 13 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (𝐵 ∪ 𝐶) ∈ V)
102		snex 4908	. . . . . . . . . . . . . 14 ⊢ {𝑥} ∈ V
103	13	adantr 481	. . . . . . . . . . . . . 14 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → 𝐴 ∈ V)
104		xpexg 6960	. . . . . . . . . . . . . 14 ⊢ (({𝑥} ∈ V ∧ 𝐴 ∈ V) → ({𝑥} × 𝐴) ∈ V)
105	102, 103, 104	sylancr 695	. . . . . . . . . . . . 13 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → ({𝑥} × 𝐴) ∈ V)
106		f1imaen2g 8017	. . . . . . . . . . . . 13 ⊢ (((◡𝑓:(𝐴 × 𝐴)–1-1→(𝐵 ∪ 𝐶) ∧ (𝐵 ∪ 𝐶) ∈ V) ∧ (({𝑥} × 𝐴) ⊆ (𝐴 × 𝐴) ∧ ({𝑥} × 𝐴) ∈ V)) → (◡𝑓 “ ({𝑥} × 𝐴)) ≈ ({𝑥} × 𝐴))
107	100, 101, 68, 105, 106	syl22anc 1327	. . . . . . . . . . . 12 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (◡𝑓 “ ({𝑥} × 𝐴)) ≈ ({𝑥} × 𝐴))
108		vex 3203	. . . . . . . . . . . . 13 ⊢ 𝑥 ∈ V
109		xpsnen2g 8053	. . . . . . . . . . . . 13 ⊢ ((𝑥 ∈ V ∧ 𝐴 ∈ V) → ({𝑥} × 𝐴) ≈ 𝐴)
110	108, 103, 109	sylancr 695	. . . . . . . . . . . 12 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → ({𝑥} × 𝐴) ≈ 𝐴)
111		entr 8008	. . . . . . . . . . . 12 ⊢ (((◡𝑓 “ ({𝑥} × 𝐴)) ≈ ({𝑥} × 𝐴) ∧ ({𝑥} × 𝐴) ≈ 𝐴) → (◡𝑓 “ ({𝑥} × 𝐴)) ≈ 𝐴)
112	107, 110, 111	syl2anc 693	. . . . . . . . . . 11 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (◡𝑓 “ ({𝑥} × 𝐴)) ≈ 𝐴)
113		domen1 8102	. . . . . . . . . . 11 ⊢ ((◡𝑓 “ ({𝑥} × 𝐴)) ≈ 𝐴 → ((◡𝑓 “ ({𝑥} × 𝐴)) ≼ 𝐶 ↔ 𝐴 ≼ 𝐶))
114	112, 113	syl 17	. . . . . . . . . 10 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → ((◡𝑓 “ ({𝑥} × 𝐴)) ≼ 𝐶 ↔ 𝐴 ≼ 𝐶))
115	96, 114	mpbid 222	. . . . . . . . 9 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → 𝐴 ≼ 𝐶)
116	115	olcd 408	. . . . . . . 8 ⊢ ((𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) ∧ 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵))) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶))
117	116	ex 450	. . . . . . 7 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶)))
118	117	exlimdv 1861	. . . . . 6 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (∃𝑥 𝑥 ∈ (𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶)))
119	45, 118	syl5bi 232	. . . . 5 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → ((𝐴 ∖ (((1st ↾ (𝐴 × 𝐴)) ∘ 𝑓) “ 𝐵)) ≠ ∅ → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶)))
120	44, 119	pm2.61dne 2880	. . . 4 ⊢ (𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶))
121	120	exlimiv 1858	. . 3 ⊢ (∃𝑓 𝑓:(𝐵 ∪ 𝐶)–1-1-onto→(𝐴 × 𝐴) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶))
122	2, 121	sylbi 207	. 2 ⊢ ((𝐵 ∪ 𝐶) ≈ (𝐴 × 𝐴) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶))
123	1, 122	syl 17	1 ⊢ ((𝐴 × 𝐴) ≈ (𝐵 ∪ 𝐶) → (𝐴 ≼* 𝐵 ∨ 𝐴 ≼ 𝐶))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 196   ∨ wo 383   ∧ wa 384   = wceq 1483  ∃wex 1704   ∈ wcel 1990   ≠ wne 2794  Vcvv 3200   ∖ cdif 3571   ∪ cun 3572   ⊆ wss 3574  ∅c0 3915  {csn 4177   class class class wbr 4653   × cxp 5112  ^◡ccnv 5113  dom cdm 5114  ran crn 5115   ↾ cres 5116   “ cima 5117   ∘ ccom 5118  Fun wfun 5882   Fn wfn 5883  ⟶wf 5884  –1-1→wf1 5885  –onto→wfo 5886  –1-1-onto→wf1o 5887  ‘cfv 5888  1^st c1st 7166   ≈ cen 7952   ≼ cdom 7953   ≼^* cwdom 8462

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-ral 2917  df-rex 2918  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-op 4184  df-uni 4437  df-int 4476  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-id 5024  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-1st 7168  df-2nd 7169  df-er 7742  df-en 7956  df-dom 7957  df-sdom 7958  df-wdom 8464

This theorem is referenced by:  unxpwdom  8494  ttac  37603