Theorem prjspval 43457

Description: Value of the projective space function, which is also known as the projectivization of 𝑉. (Contributed by Steven Nguyen, 29-Apr-2023.)

Hypotheses

Ref	Expression
prjspval.b	⊢ 𝐵 = ((Base‘𝑉) ∖ {(0g‘𝑉)})
prjspval.x	⊢ · = ( ·𝑠 ‘𝑉)
prjspval.s	⊢ 𝑆 = (Scalar‘𝑉)
prjspval.k	⊢ 𝐾 = (Base‘𝑆)

Assertion

Ref	Expression
prjspval	⊢ (𝑉 ∈ LVec → (ℙ𝕣𝕠𝕛‘𝑉) = (𝐵 / {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦))}))

Distinct variable group:   𝑥,𝑙,𝑦,𝑉

Allowed substitution hints:   𝐵(𝑥, 𝑦, 𝑙)   𝑆(𝑥, 𝑦, 𝑙)   · (𝑥, 𝑦, 𝑙)   𝐾(𝑥, 𝑦, 𝑙)

Proof of Theorem prjspval

Dummy variables 𝑏 𝑣 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		fvex 6895	. . . . 5 ⊢ (Base‘𝑣) ∈ V
2	1	difexi 5299	. . . 4 ⊢ ((Base‘𝑣) ∖ {(0g‘𝑣)}) ∈ V
3	2	a1i 11	. . 3 ⊢ (𝑣 = 𝑉 → ((Base‘𝑣) ∖ {(0g‘𝑣)}) ∈ V)
4		fveq2 6882	. . . . . . . . 9 ⊢ (𝑣 = 𝑉 → (Base‘𝑣) = (Base‘𝑉))
5		fveq2 6882	. . . . . . . . . 10 ⊢ (𝑣 = 𝑉 → (0g‘𝑣) = (0g‘𝑉))
6	5	sneqd 4599	. . . . . . . . 9 ⊢ (𝑣 = 𝑉 → {(0g‘𝑣)} = {(0g‘𝑉)})
7	4, 6	difeq12d 4078	. . . . . . . 8 ⊢ (𝑣 = 𝑉 → ((Base‘𝑣) ∖ {(0g‘𝑣)}) = ((Base‘𝑉) ∖ {(0g‘𝑉)}))
8		prjspval.b	. . . . . . . 8 ⊢ 𝐵 = ((Base‘𝑉) ∖ {(0g‘𝑉)})
9	7, 8	eqtr4di 2815	. . . . . . 7 ⊢ (𝑣 = 𝑉 → ((Base‘𝑣) ∖ {(0g‘𝑣)}) = 𝐵)
10	9	eqeq2d 2773	. . . . . 6 ⊢ (𝑣 = 𝑉 → (𝑏 = ((Base‘𝑣) ∖ {(0g‘𝑣)}) ↔ 𝑏 = 𝐵))
11	10	biimpd 232	. . . . 5 ⊢ (𝑣 = 𝑉 → (𝑏 = ((Base‘𝑣) ∖ {(0g‘𝑣)}) → 𝑏 = 𝐵))
12	11	imp 412	. . . 4 ⊢ ((𝑣 = 𝑉 ∧ 𝑏 = ((Base‘𝑣) ∖ {(0g‘𝑣)})) → 𝑏 = 𝐵)
13	11	imdistani 579	. . . . . 6 ⊢ ((𝑣 = 𝑉 ∧ 𝑏 = ((Base‘𝑣) ∖ {(0g‘𝑣)})) → (𝑣 = 𝑉 ∧ 𝑏 = 𝐵))
14		eleq2 2851	. . . . . . . 8 ⊢ (𝑏 = 𝐵 → (𝑥 ∈ 𝑏 ↔ 𝑥 ∈ 𝐵))
15		eleq2 2851	. . . . . . . 8 ⊢ (𝑏 = 𝐵 → (𝑦 ∈ 𝑏 ↔ 𝑦 ∈ 𝐵))
16	14, 15	anbi12d 644	. . . . . . 7 ⊢ (𝑏 = 𝐵 → ((𝑥 ∈ 𝑏 ∧ 𝑦 ∈ 𝑏) ↔ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)))
17		fveq2 6882	. . . . . . . . . . 11 ⊢ (𝑣 = 𝑉 → (Scalar‘𝑣) = (Scalar‘𝑉))
18		prjspval.s	. . . . . . . . . . 11 ⊢ 𝑆 = (Scalar‘𝑉)
19	17, 18	eqtr4di 2815	. . . . . . . . . 10 ⊢ (𝑣 = 𝑉 → (Scalar‘𝑣) = 𝑆)
20	19	fveq2d 6886	. . . . . . . . 9 ⊢ (𝑣 = 𝑉 → (Base‘(Scalar‘𝑣)) = (Base‘𝑆))
21		prjspval.k	. . . . . . . . 9 ⊢ 𝐾 = (Base‘𝑆)
22	20, 21	eqtr4di 2815	. . . . . . . 8 ⊢ (𝑣 = 𝑉 → (Base‘(Scalar‘𝑣)) = 𝐾)
23		fveq2 6882	. . . . . . . . . . 11 ⊢ (𝑣 = 𝑉 → ( ·𝑠 ‘𝑣) = ( ·𝑠 ‘𝑉))
24		prjspval.x	. . . . . . . . . . 11 ⊢ · = ( ·𝑠 ‘𝑉)
25	23, 24	eqtr4di 2815	. . . . . . . . . 10 ⊢ (𝑣 = 𝑉 → ( ·𝑠 ‘𝑣) = · )
26	25	oveqd 7434	. . . . . . . . 9 ⊢ (𝑣 = 𝑉 → (𝑙( ·𝑠 ‘𝑣)𝑦) = (𝑙 · 𝑦))
27	26	eqeq2d 2773	. . . . . . . 8 ⊢ (𝑣 = 𝑉 → (𝑥 = (𝑙( ·𝑠 ‘𝑣)𝑦) ↔ 𝑥 = (𝑙 · 𝑦)))
28	22, 27	rexeqbidv 3337	. . . . . . 7 ⊢ (𝑣 = 𝑉 → (∃𝑙 ∈ (Base‘(Scalar‘𝑣))𝑥 = (𝑙( ·𝑠 ‘𝑣)𝑦) ↔ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦)))
29	16, 28	bi2anan9r 651	. . . . . 6 ⊢ ((𝑣 = 𝑉 ∧ 𝑏 = 𝐵) → (((𝑥 ∈ 𝑏 ∧ 𝑦 ∈ 𝑏) ∧ ∃𝑙 ∈ (Base‘(Scalar‘𝑣))𝑥 = (𝑙( ·𝑠 ‘𝑣)𝑦)) ↔ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦))))
30	13, 29	syl 18	. . . . 5 ⊢ ((𝑣 = 𝑉 ∧ 𝑏 = ((Base‘𝑣) ∖ {(0g‘𝑣)})) → (((𝑥 ∈ 𝑏 ∧ 𝑦 ∈ 𝑏) ∧ ∃𝑙 ∈ (Base‘(Scalar‘𝑣))𝑥 = (𝑙( ·𝑠 ‘𝑣)𝑦)) ↔ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦))))
31	30	opabbidv 5175	. . . 4 ⊢ ((𝑣 = 𝑉 ∧ 𝑏 = ((Base‘𝑣) ∖ {(0g‘𝑣)})) → {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝑏 ∧ 𝑦 ∈ 𝑏) ∧ ∃𝑙 ∈ (Base‘(Scalar‘𝑣))𝑥 = (𝑙( ·𝑠 ‘𝑣)𝑦))} = {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦))})
32	12, 31	qseq12d 43115	. . 3 ⊢ ((𝑣 = 𝑉 ∧ 𝑏 = ((Base‘𝑣) ∖ {(0g‘𝑣)})) → (𝑏 / {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝑏 ∧ 𝑦 ∈ 𝑏) ∧ ∃𝑙 ∈ (Base‘(Scalar‘𝑣))𝑥 = (𝑙( ·𝑠 ‘𝑣)𝑦))}) = (𝐵 / {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦))}))
33	3, 32	csbied 3886	. 2 ⊢ (𝑣 = 𝑉 → ⦋((Base‘𝑣) ∖ {(0g‘𝑣)}) / 𝑏⦌(𝑏 / {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝑏 ∧ 𝑦 ∈ 𝑏) ∧ ∃𝑙 ∈ (Base‘(Scalar‘𝑣))𝑥 = (𝑙( ·𝑠 ‘𝑣)𝑦))}) = (𝐵 / {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦))}))
34		df-prjsp 43456	. 2 ⊢ ℙ𝕣𝕠𝕛 = (𝑣 ∈ LVec ↦ ⦋((Base‘𝑣) ∖ {(0g‘𝑣)}) / 𝑏⦌(𝑏 / {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝑏 ∧ 𝑦 ∈ 𝑏) ∧ ∃𝑙 ∈ (Base‘(Scalar‘𝑣))𝑥 = (𝑙( ·𝑠 ‘𝑣)𝑦))}))
35		fvex 6895	. . . . 5 ⊢ (Base‘𝑉) ∈ V
36	35	difexi 5299	. . . 4 ⊢ ((Base‘𝑉) ∖ {(0g‘𝑉)}) ∈ V
37	8, 36	eqeltri 2858	. . 3 ⊢ 𝐵 ∈ V
38	37	qsex 8776	. 2 ⊢ (𝐵 / {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦))}) ∈ V
39	33, 34, 38	fvmpt 6990	1 ⊢ (𝑉 ∈ LVec → (ℙ𝕣𝕠𝕛‘𝑉) = (𝐵 / {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ ∃𝑙 ∈ 𝐾 𝑥 = (𝑙 · 𝑦))}))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570   ∈ wcel 2145  ∃wrex 3088  Vcvv 3453  ⦋csb 3850   ∖ cdif 3899  {csn 4587  {copab 5171  ‘cfv 6537  (class class class)co 7417   / cqs 8699  Basecbs 17307  Scalarcsca 17351   ·_𝑠 cvsca 17352  0_gc0g 17530  LVecclvec 21292  ℙ𝕣𝕠𝕛cprjsp 43455

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2734  ax-rep 5236  ax-sep 5255  ax-nul 5267  ax-pr 5402

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3079  df-rex 3089  df-rab 3415  df-v 3455  df-sbc 3743  df-csb 3851  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-nul 4283  df-if 4486  df-sn 4588  df-pr 4590  df-op 4594  df-uni 4871  df-br 5108  df-opab 5172  df-mpt 5191  df-id 5554  df-xp 5665  df-rel 5666  df-cnv 5667  df-co 5668  df-dm 5669  df-rn 5670  df-res 5671  df-ima 5672  df-iota 6493  df-fun 6539  df-fv 6545  df-ov 7420  df-ec 8702  df-qs 8706  df-prjsp 43456

This theorem is used by:  prjspval2  43467  prjspnval2  43472