Theorem fvineqsnf1 37916

Description: A theorem about functions where the image of every point intersects the domain only at that point. If 𝐽 is a topology and 𝐴 is a set with no limit points, then there exists an 𝐹 such that this antecedent is true. See nlpfvineqsn 37915 for a proof of this fact. (Contributed by ML, 23-Mar-2021.)

Assertion

Ref	Expression
fvineqsnf1	⊢ ((𝐹:𝐴⟶𝐽 ∧ ∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝}) → 𝐹:𝐴–1-1→𝐽)

Distinct variable groups:   𝐴,𝑝   𝐹,𝑝

Allowed substitution hint:   𝐽(𝑝)

Proof of Theorem fvineqsnf1

Dummy variable 𝑞 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		fveq2 6871	. . . . . . . . . 10 ⊢ (𝑝 = 𝑞 → (𝐹‘𝑝) = (𝐹‘𝑞))
2	1	ineq1d 4174	. . . . . . . . 9 ⊢ (𝑝 = 𝑞 → ((𝐹‘𝑝) ∩ 𝐴) = ((𝐹‘𝑞) ∩ 𝐴))
3		sneq 4595	. . . . . . . . 9 ⊢ (𝑝 = 𝑞 → {𝑝} = {𝑞})
4	2, 3	eqeq12d 2781	. . . . . . . 8 ⊢ (𝑝 = 𝑞 → (((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ↔ ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}))
5	4	cbvralvw 3243	. . . . . . 7 ⊢ (∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ↔ ∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞})
6	5	biimpi 219	. . . . . 6 ⊢ (∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → ∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞})
7		ax-5 1933	. . . . . . . 8 ⊢ (∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → ∀𝑞∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝})
8		alral 3094	. . . . . . . 8 ⊢ (∀𝑞∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → ∀𝑞 ∈ 𝐴 ∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝})
9		ralcom 3293	. . . . . . . . 9 ⊢ (∀𝑞 ∈ 𝐴 ∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ↔ ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝})
10	9	biimpi 219	. . . . . . . 8 ⊢ (∀𝑞 ∈ 𝐴 ∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝})
11	7, 8, 10	3syl 19	. . . . . . 7 ⊢ (∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝})
12		ax-5 1933	. . . . . . . 8 ⊢ (∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞} → ∀𝑝∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞})
13		alral 3094	. . . . . . . 8 ⊢ (∀𝑝∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞} → ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞})
14	12, 13	syl 18	. . . . . . 7 ⊢ (∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞} → ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞})
15	11, 14	anim12i 624	. . . . . 6 ⊢ ((∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}) → (∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}))
16	6, 15	mpdan 699	. . . . 5 ⊢ (∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → (∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}))
17		r19.26-2 3150	. . . . 5 ⊢ (∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 (((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}) ↔ (∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}))
18	16, 17	sylibr 237	. . . 4 ⊢ (∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 (((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}))
19		ineq1 4168	. . . . . . 7 ⊢ ((𝐹‘𝑝) = (𝐹‘𝑞) → ((𝐹‘𝑝) ∩ 𝐴) = ((𝐹‘𝑞) ∩ 𝐴))
20		eqeq1 2769	. . . . . . . . 9 ⊢ (((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → (((𝐹‘𝑝) ∩ 𝐴) = ((𝐹‘𝑞) ∩ 𝐴) ↔ {𝑝} = ((𝐹‘𝑞) ∩ 𝐴)))
21		eqcom 2772	. . . . . . . . 9 ⊢ ({𝑝} = ((𝐹‘𝑞) ∩ 𝐴) ↔ ((𝐹‘𝑞) ∩ 𝐴) = {𝑝})
22	20, 21	bitrdi 290	. . . . . . . 8 ⊢ (((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → (((𝐹‘𝑝) ∩ 𝐴) = ((𝐹‘𝑞) ∩ 𝐴) ↔ ((𝐹‘𝑞) ∩ 𝐴) = {𝑝}))
23		eqeq1 2769	. . . . . . . . 9 ⊢ (((𝐹‘𝑞) ∩ 𝐴) = {𝑞} → (((𝐹‘𝑞) ∩ 𝐴) = {𝑝} ↔ {𝑞} = {𝑝}))
24		eqcom 2772	. . . . . . . . . 10 ⊢ ({𝑞} = {𝑝} ↔ {𝑝} = {𝑞})
25		vex 3461	. . . . . . . . . . 11 ⊢ 𝑝 ∈ V
26		sneqbg 4804	. . . . . . . . . . 11 ⊢ (𝑝 ∈ V → ({𝑝} = {𝑞} ↔ 𝑝 = 𝑞))
27	25, 26	ax-mp 5	. . . . . . . . . 10 ⊢ ({𝑝} = {𝑞} ↔ 𝑝 = 𝑞)
28	24, 27	bitri 278	. . . . . . . . 9 ⊢ ({𝑞} = {𝑝} ↔ 𝑝 = 𝑞)
29	23, 28	bitrdi 290	. . . . . . . 8 ⊢ (((𝐹‘𝑞) ∩ 𝐴) = {𝑞} → (((𝐹‘𝑞) ∩ 𝐴) = {𝑝} ↔ 𝑝 = 𝑞))
30	22, 29	sylan9bb 518	. . . . . . 7 ⊢ ((((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}) → (((𝐹‘𝑝) ∩ 𝐴) = ((𝐹‘𝑞) ∩ 𝐴) ↔ 𝑝 = 𝑞))
31	19, 30	imbitrid 247	. . . . . 6 ⊢ ((((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}) → ((𝐹‘𝑝) = (𝐹‘𝑞) → 𝑝 = 𝑞))
32	31	ralimi 3102	. . . . 5 ⊢ (∀𝑞 ∈ 𝐴 (((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}) → ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) = (𝐹‘𝑞) → 𝑝 = 𝑞))
33	32	ralimi 3102	. . . 4 ⊢ (∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 (((𝐹‘𝑝) ∩ 𝐴) = {𝑝} ∧ ((𝐹‘𝑞) ∩ 𝐴) = {𝑞}) → ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) = (𝐹‘𝑞) → 𝑝 = 𝑞))
34	18, 33	syl 18	. . 3 ⊢ (∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝} → ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) = (𝐹‘𝑞) → 𝑝 = 𝑞))
35	34	anim2i 628	. 2 ⊢ ((𝐹:𝐴⟶𝐽 ∧ ∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝}) → (𝐹:𝐴⟶𝐽 ∧ ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) = (𝐹‘𝑞) → 𝑝 = 𝑞)))
36		dff13 7242	. 2 ⊢ (𝐹:𝐴–1-1→𝐽 ↔ (𝐹:𝐴⟶𝐽 ∧ ∀𝑝 ∈ 𝐴 ∀𝑞 ∈ 𝐴 ((𝐹‘𝑝) = (𝐹‘𝑞) → 𝑝 = 𝑞)))
37	35, 36	sylibr 237	1 ⊢ ((𝐹:𝐴⟶𝐽 ∧ ∀𝑝 ∈ 𝐴 ((𝐹‘𝑝) ∩ 𝐴) = {𝑝}) → 𝐹:𝐴–1-1→𝐽)

Syntax hints:   → wi 4   ↔ wb 209   ∧ wa 400  ∀wal 1561   = wceq 1563   ∈ wcel 2145  ∀wral 3079  Vcvv 3457   ∩ cin 3906  {csn 4585  ⟶wf 6521  –1-1→wf1 6522  ‘cfv 6525

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1818  ax-4 1832  ax-5 1933  ax-6 1990  ax-7 2031  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2737  ax-sep 5251  ax-nul 5261  ax-pr 5395

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1103  df-tru 1566  df-fal 1576  df-ex 1803  df-nf 1807  df-sb 2094  df-mo 2569  df-eu 2599  df-clab 2744  df-cleq 2757  df-clel 2840  df-ne 2961  df-ral 3080  df-rex 3090  df-rab 3418  df-v 3459  df-dif 3910  df-un 3912  df-in 3914  df-ss 3924  df-nul 4289  df-if 4484  df-sn 4586  df-pr 4588  df-op 4592  df-uni 4869  df-br 5106  df-opab 5168  df-id 5547  df-xp 5658  df-rel 5659  df-cnv 5660  df-co 5661  df-dm 5662  df-iota 6481  df-fun 6527  df-fn 6528  df-f 6529  df-f1 6530  df-fv 6533

This theorem is referenced by:  fvineqsneu  37917  pibt2  37923