Theorem cnref1o 9771

Description: There is a natural one-to-one mapping from (ℝ × ℝ) to ℂ, where we map ⟨𝑥, 𝑦⟩ to (𝑥 + (i · 𝑦)). In our construction of the complex numbers, this is in fact our definition of ℂ (see df-c 7930), but in the axiomatic treatment we can only show that there is the expected mapping between these two sets. (Contributed by Mario Carneiro, 16-Jun-2013.) (Revised by Mario Carneiro, 17-Feb-2014.)

Hypothesis

Ref	Expression
cnref1o.1	⊢ 𝐹 = (𝑥 ∈ ℝ, 𝑦 ∈ ℝ ↦ (𝑥 + (i · 𝑦)))

Assertion

Ref	Expression
cnref1o	⊢ 𝐹:(ℝ × ℝ)–1-1-onto→ℂ

Distinct variable group:   𝑥,𝑦

Allowed substitution hints:   𝐹(𝑥,𝑦)

Proof of Theorem cnref1o

Dummy variables 𝑢 𝑣 𝑤 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		simpl 109	. . . . . . . 8 ⊢ ((𝑥 ∈ ℝ ∧ 𝑦 ∈ ℝ) → 𝑥 ∈ ℝ)
2	1	recnd 8100	. . . . . . 7 ⊢ ((𝑥 ∈ ℝ ∧ 𝑦 ∈ ℝ) → 𝑥 ∈ ℂ)
3		ax-icn 8019	. . . . . . . . 9 ⊢ i ∈ ℂ
4	3	a1i 9	. . . . . . . 8 ⊢ ((𝑥 ∈ ℝ ∧ 𝑦 ∈ ℝ) → i ∈ ℂ)
5		simpr 110	. . . . . . . . 9 ⊢ ((𝑥 ∈ ℝ ∧ 𝑦 ∈ ℝ) → 𝑦 ∈ ℝ)
6	5	recnd 8100	. . . . . . . 8 ⊢ ((𝑥 ∈ ℝ ∧ 𝑦 ∈ ℝ) → 𝑦 ∈ ℂ)
7	4, 6	mulcld 8092	. . . . . . 7 ⊢ ((𝑥 ∈ ℝ ∧ 𝑦 ∈ ℝ) → (i · 𝑦) ∈ ℂ)
8	2, 7	addcld 8091	. . . . . 6 ⊢ ((𝑥 ∈ ℝ ∧ 𝑦 ∈ ℝ) → (𝑥 + (i · 𝑦)) ∈ ℂ)
9	8	rgen2a 2559	. . . . 5 ⊢ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 + (i · 𝑦)) ∈ ℂ
10		cnref1o.1	. . . . . 6 ⊢ 𝐹 = (𝑥 ∈ ℝ, 𝑦 ∈ ℝ ↦ (𝑥 + (i · 𝑦)))
11	10	fnmpo 6287	. . . . 5 ⊢ (∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 + (i · 𝑦)) ∈ ℂ → 𝐹 Fn (ℝ × ℝ))
12	9, 11	ax-mp 5	. . . 4 ⊢ 𝐹 Fn (ℝ × ℝ)
13		1st2nd2 6260	. . . . . . . . 9 ⊢ (𝑧 ∈ (ℝ × ℝ) → 𝑧 = ⟨(1st ‘𝑧), (2nd ‘𝑧)⟩)
14	13	fveq2d 5579	. . . . . . . 8 ⊢ (𝑧 ∈ (ℝ × ℝ) → (𝐹‘𝑧) = (𝐹‘⟨(1st ‘𝑧), (2nd ‘𝑧)⟩))
15		df-ov 5946	. . . . . . . 8 ⊢ ((1st ‘𝑧)𝐹(2nd ‘𝑧)) = (𝐹‘⟨(1st ‘𝑧), (2nd ‘𝑧)⟩)
16	14, 15	eqtr4di 2255	. . . . . . 7 ⊢ (𝑧 ∈ (ℝ × ℝ) → (𝐹‘𝑧) = ((1st ‘𝑧)𝐹(2nd ‘𝑧)))
17		xp1st 6250	. . . . . . . 8 ⊢ (𝑧 ∈ (ℝ × ℝ) → (1st ‘𝑧) ∈ ℝ)
18		xp2nd 6251	. . . . . . . 8 ⊢ (𝑧 ∈ (ℝ × ℝ) → (2nd ‘𝑧) ∈ ℝ)
19	17	recnd 8100	. . . . . . . . 9 ⊢ (𝑧 ∈ (ℝ × ℝ) → (1st ‘𝑧) ∈ ℂ)
20	3	a1i 9	. . . . . . . . . 10 ⊢ (𝑧 ∈ (ℝ × ℝ) → i ∈ ℂ)
21	18	recnd 8100	. . . . . . . . . 10 ⊢ (𝑧 ∈ (ℝ × ℝ) → (2nd ‘𝑧) ∈ ℂ)
22	20, 21	mulcld 8092	. . . . . . . . 9 ⊢ (𝑧 ∈ (ℝ × ℝ) → (i · (2nd ‘𝑧)) ∈ ℂ)
23	19, 22	addcld 8091	. . . . . . . 8 ⊢ (𝑧 ∈ (ℝ × ℝ) → ((1st ‘𝑧) + (i · (2nd ‘𝑧))) ∈ ℂ)
24		oveq1 5950	. . . . . . . . 9 ⊢ (𝑥 = (1st ‘𝑧) → (𝑥 + (i · 𝑦)) = ((1st ‘𝑧) + (i · 𝑦)))
25		oveq2 5951	. . . . . . . . . 10 ⊢ (𝑦 = (2nd ‘𝑧) → (i · 𝑦) = (i · (2nd ‘𝑧)))
26	25	oveq2d 5959	. . . . . . . . 9 ⊢ (𝑦 = (2nd ‘𝑧) → ((1st ‘𝑧) + (i · 𝑦)) = ((1st ‘𝑧) + (i · (2nd ‘𝑧))))
27	24, 26, 10	ovmpog 6079	. . . . . . . 8 ⊢ (((1st ‘𝑧) ∈ ℝ ∧ (2nd ‘𝑧) ∈ ℝ ∧ ((1st ‘𝑧) + (i · (2nd ‘𝑧))) ∈ ℂ) → ((1st ‘𝑧)𝐹(2nd ‘𝑧)) = ((1st ‘𝑧) + (i · (2nd ‘𝑧))))
28	17, 18, 23, 27	syl3anc 1249	. . . . . . 7 ⊢ (𝑧 ∈ (ℝ × ℝ) → ((1st ‘𝑧)𝐹(2nd ‘𝑧)) = ((1st ‘𝑧) + (i · (2nd ‘𝑧))))
29	16, 28	eqtrd 2237	. . . . . 6 ⊢ (𝑧 ∈ (ℝ × ℝ) → (𝐹‘𝑧) = ((1st ‘𝑧) + (i · (2nd ‘𝑧))))
30	29, 23	eqeltrd 2281	. . . . 5 ⊢ (𝑧 ∈ (ℝ × ℝ) → (𝐹‘𝑧) ∈ ℂ)
31	30	rgen 2558	. . . 4 ⊢ ∀𝑧 ∈ (ℝ × ℝ)(𝐹‘𝑧) ∈ ℂ
32		ffnfv 5737	. . . 4 ⊢ (𝐹:(ℝ × ℝ)⟶ℂ ↔ (𝐹 Fn (ℝ × ℝ) ∧ ∀𝑧 ∈ (ℝ × ℝ)(𝐹‘𝑧) ∈ ℂ))
33	12, 31, 32	mpbir2an 944	. . 3 ⊢ 𝐹:(ℝ × ℝ)⟶ℂ
34	17, 18	jca 306	. . . . . . 7 ⊢ (𝑧 ∈ (ℝ × ℝ) → ((1st ‘𝑧) ∈ ℝ ∧ (2nd ‘𝑧) ∈ ℝ))
35		xp1st 6250	. . . . . . . 8 ⊢ (𝑤 ∈ (ℝ × ℝ) → (1st ‘𝑤) ∈ ℝ)
36		xp2nd 6251	. . . . . . . 8 ⊢ (𝑤 ∈ (ℝ × ℝ) → (2nd ‘𝑤) ∈ ℝ)
37	35, 36	jca 306	. . . . . . 7 ⊢ (𝑤 ∈ (ℝ × ℝ) → ((1st ‘𝑤) ∈ ℝ ∧ (2nd ‘𝑤) ∈ ℝ))
38		cru 8674	. . . . . . 7 ⊢ ((((1st ‘𝑧) ∈ ℝ ∧ (2nd ‘𝑧) ∈ ℝ) ∧ ((1st ‘𝑤) ∈ ℝ ∧ (2nd ‘𝑤) ∈ ℝ)) → (((1st ‘𝑧) + (i · (2nd ‘𝑧))) = ((1st ‘𝑤) + (i · (2nd ‘𝑤))) ↔ ((1st ‘𝑧) = (1st ‘𝑤) ∧ (2nd ‘𝑧) = (2nd ‘𝑤))))
39	34, 37, 38	syl2an 289	. . . . . 6 ⊢ ((𝑧 ∈ (ℝ × ℝ) ∧ 𝑤 ∈ (ℝ × ℝ)) → (((1st ‘𝑧) + (i · (2nd ‘𝑧))) = ((1st ‘𝑤) + (i · (2nd ‘𝑤))) ↔ ((1st ‘𝑧) = (1st ‘𝑤) ∧ (2nd ‘𝑧) = (2nd ‘𝑤))))
40		fveq2 5575	. . . . . . . . 9 ⊢ (𝑧 = 𝑤 → (𝐹‘𝑧) = (𝐹‘𝑤))
41		fveq2 5575	. . . . . . . . . 10 ⊢ (𝑧 = 𝑤 → (1st ‘𝑧) = (1st ‘𝑤))
42		fveq2 5575	. . . . . . . . . . 11 ⊢ (𝑧 = 𝑤 → (2nd ‘𝑧) = (2nd ‘𝑤))
43	42	oveq2d 5959	. . . . . . . . . 10 ⊢ (𝑧 = 𝑤 → (i · (2nd ‘𝑧)) = (i · (2nd ‘𝑤)))
44	41, 43	oveq12d 5961	. . . . . . . . 9 ⊢ (𝑧 = 𝑤 → ((1st ‘𝑧) + (i · (2nd ‘𝑧))) = ((1st ‘𝑤) + (i · (2nd ‘𝑤))))
45	40, 44	eqeq12d 2219	. . . . . . . 8 ⊢ (𝑧 = 𝑤 → ((𝐹‘𝑧) = ((1st ‘𝑧) + (i · (2nd ‘𝑧))) ↔ (𝐹‘𝑤) = ((1st ‘𝑤) + (i · (2nd ‘𝑤)))))
46	45, 29	vtoclga 2838	. . . . . . 7 ⊢ (𝑤 ∈ (ℝ × ℝ) → (𝐹‘𝑤) = ((1st ‘𝑤) + (i · (2nd ‘𝑤))))
47	29, 46	eqeqan12d 2220	. . . . . 6 ⊢ ((𝑧 ∈ (ℝ × ℝ) ∧ 𝑤 ∈ (ℝ × ℝ)) → ((𝐹‘𝑧) = (𝐹‘𝑤) ↔ ((1st ‘𝑧) + (i · (2nd ‘𝑧))) = ((1st ‘𝑤) + (i · (2nd ‘𝑤)))))
48		1st2nd2 6260	. . . . . . . 8 ⊢ (𝑤 ∈ (ℝ × ℝ) → 𝑤 = ⟨(1st ‘𝑤), (2nd ‘𝑤)⟩)
49	13, 48	eqeqan12d 2220	. . . . . . 7 ⊢ ((𝑧 ∈ (ℝ × ℝ) ∧ 𝑤 ∈ (ℝ × ℝ)) → (𝑧 = 𝑤 ↔ ⟨(1st ‘𝑧), (2nd ‘𝑧)⟩ = ⟨(1st ‘𝑤), (2nd ‘𝑤)⟩))
50		vex 2774	. . . . . . . . 9 ⊢ 𝑧 ∈ V
51		1stexg 6252	. . . . . . . . 9 ⊢ (𝑧 ∈ V → (1st ‘𝑧) ∈ V)
52	50, 51	ax-mp 5	. . . . . . . 8 ⊢ (1st ‘𝑧) ∈ V
53		2ndexg 6253	. . . . . . . . 9 ⊢ (𝑧 ∈ V → (2nd ‘𝑧) ∈ V)
54	50, 53	ax-mp 5	. . . . . . . 8 ⊢ (2nd ‘𝑧) ∈ V
55	52, 54	opth 4280	. . . . . . 7 ⊢ (⟨(1st ‘𝑧), (2nd ‘𝑧)⟩ = ⟨(1st ‘𝑤), (2nd ‘𝑤)⟩ ↔ ((1st ‘𝑧) = (1st ‘𝑤) ∧ (2nd ‘𝑧) = (2nd ‘𝑤)))
56	49, 55	bitrdi 196	. . . . . 6 ⊢ ((𝑧 ∈ (ℝ × ℝ) ∧ 𝑤 ∈ (ℝ × ℝ)) → (𝑧 = 𝑤 ↔ ((1st ‘𝑧) = (1st ‘𝑤) ∧ (2nd ‘𝑧) = (2nd ‘𝑤))))
57	39, 47, 56	3bitr4d 220	. . . . 5 ⊢ ((𝑧 ∈ (ℝ × ℝ) ∧ 𝑤 ∈ (ℝ × ℝ)) → ((𝐹‘𝑧) = (𝐹‘𝑤) ↔ 𝑧 = 𝑤))
58	57	biimpd 144	. . . 4 ⊢ ((𝑧 ∈ (ℝ × ℝ) ∧ 𝑤 ∈ (ℝ × ℝ)) → ((𝐹‘𝑧) = (𝐹‘𝑤) → 𝑧 = 𝑤))
59	58	rgen2a 2559	. . 3 ⊢ ∀𝑧 ∈ (ℝ × ℝ)∀𝑤 ∈ (ℝ × ℝ)((𝐹‘𝑧) = (𝐹‘𝑤) → 𝑧 = 𝑤)
60		dff13 5836	. . 3 ⊢ (𝐹:(ℝ × ℝ)–1-1→ℂ ↔ (𝐹:(ℝ × ℝ)⟶ℂ ∧ ∀𝑧 ∈ (ℝ × ℝ)∀𝑤 ∈ (ℝ × ℝ)((𝐹‘𝑧) = (𝐹‘𝑤) → 𝑧 = 𝑤)))
61	33, 59, 60	mpbir2an 944	. 2 ⊢ 𝐹:(ℝ × ℝ)–1-1→ℂ
62		cnre 8067	. . . . . 6 ⊢ (𝑤 ∈ ℂ → ∃𝑢 ∈ ℝ ∃𝑣 ∈ ℝ 𝑤 = (𝑢 + (i · 𝑣)))
63		simpl 109	. . . . . . . . 9 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → 𝑢 ∈ ℝ)
64		simpr 110	. . . . . . . . 9 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → 𝑣 ∈ ℝ)
65	63	recnd 8100	. . . . . . . . . 10 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → 𝑢 ∈ ℂ)
66	3	a1i 9	. . . . . . . . . . 11 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → i ∈ ℂ)
67	64	recnd 8100	. . . . . . . . . . 11 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → 𝑣 ∈ ℂ)
68	66, 67	mulcld 8092	. . . . . . . . . 10 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → (i · 𝑣) ∈ ℂ)
69	65, 68	addcld 8091	. . . . . . . . 9 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → (𝑢 + (i · 𝑣)) ∈ ℂ)
70		oveq1 5950	. . . . . . . . . 10 ⊢ (𝑥 = 𝑢 → (𝑥 + (i · 𝑦)) = (𝑢 + (i · 𝑦)))
71		oveq2 5951	. . . . . . . . . . 11 ⊢ (𝑦 = 𝑣 → (i · 𝑦) = (i · 𝑣))
72	71	oveq2d 5959	. . . . . . . . . 10 ⊢ (𝑦 = 𝑣 → (𝑢 + (i · 𝑦)) = (𝑢 + (i · 𝑣)))
73	70, 72, 10	ovmpog 6079	. . . . . . . . 9 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ ∧ (𝑢 + (i · 𝑣)) ∈ ℂ) → (𝑢𝐹𝑣) = (𝑢 + (i · 𝑣)))
74	63, 64, 69, 73	syl3anc 1249	. . . . . . . 8 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → (𝑢𝐹𝑣) = (𝑢 + (i · 𝑣)))
75	74	eqeq2d 2216	. . . . . . 7 ⊢ ((𝑢 ∈ ℝ ∧ 𝑣 ∈ ℝ) → (𝑤 = (𝑢𝐹𝑣) ↔ 𝑤 = (𝑢 + (i · 𝑣))))
76	75	2rexbiia 2521	. . . . . 6 ⊢ (∃𝑢 ∈ ℝ ∃𝑣 ∈ ℝ 𝑤 = (𝑢𝐹𝑣) ↔ ∃𝑢 ∈ ℝ ∃𝑣 ∈ ℝ 𝑤 = (𝑢 + (i · 𝑣)))
77	62, 76	sylibr 134	. . . . 5 ⊢ (𝑤 ∈ ℂ → ∃𝑢 ∈ ℝ ∃𝑣 ∈ ℝ 𝑤 = (𝑢𝐹𝑣))
78		fveq2 5575	. . . . . . . 8 ⊢ (𝑧 = ⟨𝑢, 𝑣⟩ → (𝐹‘𝑧) = (𝐹‘⟨𝑢, 𝑣⟩))
79		df-ov 5946	. . . . . . . 8 ⊢ (𝑢𝐹𝑣) = (𝐹‘⟨𝑢, 𝑣⟩)
80	78, 79	eqtr4di 2255	. . . . . . 7 ⊢ (𝑧 = ⟨𝑢, 𝑣⟩ → (𝐹‘𝑧) = (𝑢𝐹𝑣))
81	80	eqeq2d 2216	. . . . . 6 ⊢ (𝑧 = ⟨𝑢, 𝑣⟩ → (𝑤 = (𝐹‘𝑧) ↔ 𝑤 = (𝑢𝐹𝑣)))
82	81	rexxp 4821	. . . . 5 ⊢ (∃𝑧 ∈ (ℝ × ℝ)𝑤 = (𝐹‘𝑧) ↔ ∃𝑢 ∈ ℝ ∃𝑣 ∈ ℝ 𝑤 = (𝑢𝐹𝑣))
83	77, 82	sylibr 134	. . . 4 ⊢ (𝑤 ∈ ℂ → ∃𝑧 ∈ (ℝ × ℝ)𝑤 = (𝐹‘𝑧))
84	83	rgen 2558	. . 3 ⊢ ∀𝑤 ∈ ℂ ∃𝑧 ∈ (ℝ × ℝ)𝑤 = (𝐹‘𝑧)
85		dffo3 5726	. . 3 ⊢ (𝐹:(ℝ × ℝ)–onto→ℂ ↔ (𝐹:(ℝ × ℝ)⟶ℂ ∧ ∀𝑤 ∈ ℂ ∃𝑧 ∈ (ℝ × ℝ)𝑤 = (𝐹‘𝑧)))
86	33, 84, 85	mpbir2an 944	. 2 ⊢ 𝐹:(ℝ × ℝ)–onto→ℂ
87		df-f1o 5277	. 2 ⊢ (𝐹:(ℝ × ℝ)–1-1-onto→ℂ ↔ (𝐹:(ℝ × ℝ)–1-1→ℂ ∧ 𝐹:(ℝ × ℝ)–onto→ℂ))
88	61, 86, 87	mpbir2an 944	1 ⊢ 𝐹:(ℝ × ℝ)–1-1-onto→ℂ

Syntax hints:   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1372   ∈ wcel 2175  ∀wral 2483  ∃wrex 2484  Vcvv 2771  ⟨cop 3635   × cxp 4672   Fn wfn 5265  ⟶wf 5266  –1-1→wf1 5267  –onto→wfo 5268  –1-1-onto→wf1o 5269  ‘cfv 5270  (class class class)co 5943   ∈ cmpo 5945  1^st c1st 6223  2^nd c2nd 6224  ℂcc 7922  ℝcr 7923  ici 7926   + caddc 7927   · cmul 7929

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-in1 615  ax-in2 616  ax-io 710  ax-5 1469  ax-7 1470  ax-gen 1471  ax-ie1 1515  ax-ie2 1516  ax-8 1526  ax-10 1527  ax-11 1528  ax-i12 1529  ax-bndl 1531  ax-4 1532  ax-17 1548  ax-i9 1552  ax-ial 1556  ax-i5r 1557  ax-13 2177  ax-14 2178  ax-ext 2186  ax-sep 4161  ax-pow 4217  ax-pr 4252  ax-un 4479  ax-setind 4584  ax-cnex 8015  ax-resscn 8016  ax-1cn 8017  ax-1re 8018  ax-icn 8019  ax-addcl 8020  ax-addrcl 8021  ax-mulcl 8022  ax-mulrcl 8023  ax-addcom 8024  ax-mulcom 8025  ax-addass 8026  ax-mulass 8027  ax-distr 8028  ax-i2m1 8029  ax-0lt1 8030  ax-1rid 8031  ax-0id 8032  ax-rnegex 8033  ax-precex 8034  ax-cnre 8035  ax-pre-ltirr 8036  ax-pre-lttrn 8038  ax-pre-apti 8039  ax-pre-ltadd 8040  ax-pre-mulgt0 8041

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1375  df-fal 1378  df-nf 1483  df-sb 1785  df-eu 2056  df-mo 2057  df-clab 2191  df-cleq 2197  df-clel 2200  df-nfc 2336  df-ne 2376  df-nel 2471  df-ral 2488  df-rex 2489  df-reu 2490  df-rab 2492  df-v 2773  df-sbc 2998  df-csb 3093  df-dif 3167  df-un 3169  df-in 3171  df-ss 3178  df-pw 3617  df-sn 3638  df-pr 3639  df-op 3641  df-uni 3850  df-iun 3928  df-br 4044  df-opab 4105  df-mpt 4106  df-id 4339  df-xp 4680  df-rel 4681  df-cnv 4682  df-co 4683  df-dm 4684  df-rn 4685  df-res 4686  df-ima 4687  df-iota 5231  df-fun 5272  df-fn 5273  df-f 5274  df-f1 5275  df-fo 5276  df-f1o 5277  df-fv 5278  df-riota 5898  df-ov 5946  df-oprab 5947  df-mpo 5948  df-1st 6225  df-2nd 6226  df-pnf 8108  df-mnf 8109  df-ltxr 8111  df-sub 8244  df-neg 8245  df-reap 8647

This theorem is referenced by:  cnrecnv  11163