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Theorem fldextrspunlem1 34105
Description: Lemma for fldextrspunfld 34106. Part of the proof of Proposition 5, Chapter 5, of [BourbakiAlg2] p. 116. (Contributed by Thierry Arnoux, 13-Oct-2025.)
Hypotheses
Ref Expression
fldextrspunfld.k 𝐾 = (𝐿s 𝐹)
fldextrspunfld.i 𝐼 = (𝐿s 𝐺)
fldextrspunfld.j 𝐽 = (𝐿s 𝐻)
fldextrspunfld.2 (𝜑𝐿 ∈ Field)
fldextrspunfld.3 (𝜑𝐹 ∈ (SubDRing‘𝐼))
fldextrspunfld.4 (𝜑𝐹 ∈ (SubDRing‘𝐽))
fldextrspunfld.5 (𝜑𝐺 ∈ (SubDRing‘𝐿))
fldextrspunfld.6 (𝜑𝐻 ∈ (SubDRing‘𝐿))
fldextrspunfld.7 (𝜑 → (𝐽[:]𝐾) ∈ ℕ0)
fldextrspunfld.n 𝑁 = (RingSpan‘𝐿)
fldextrspunfld.c 𝐶 = (𝑁‘(𝐺𝐻))
fldextrspunfld.e 𝐸 = (𝐿s 𝐶)
Assertion
Ref Expression
fldextrspunlem1 (𝜑 → (dim‘((subringAlg ‘𝐸)‘𝐺)) ≤ (𝐽[:]𝐾))

Proof of Theorem fldextrspunlem1
Dummy variables 𝑏 𝑐 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 fldextrspunfld.6 . . . . 5 (𝜑𝐻 ∈ (SubDRing‘𝐿))
2 fldextrspunfld.j . . . . . 6 𝐽 = (𝐿s 𝐻)
32sdrgdrng 20923 . . . . 5 (𝐻 ∈ (SubDRing‘𝐿) → 𝐽 ∈ DivRing)
41, 3syl 18 . . . 4 (𝜑𝐽 ∈ DivRing)
5 fldextrspunfld.4 . . . . 5 (𝜑𝐹 ∈ (SubDRing‘𝐽))
6 eqid 2765 . . . . . 6 (𝐽s 𝐹) = (𝐽s 𝐹)
76sdrgdrng 20923 . . . . 5 (𝐹 ∈ (SubDRing‘𝐽) → (𝐽s 𝐹) ∈ DivRing)
85, 7syl 18 . . . 4 (𝜑 → (𝐽s 𝐹) ∈ DivRing)
9 sdrgsubrg 20924 . . . . . 6 (𝐻 ∈ (SubDRing‘𝐿) → 𝐻 ∈ (SubRing‘𝐿))
101, 9syl 18 . . . . 5 (𝜑𝐻 ∈ (SubRing‘𝐿))
11 fldextrspunfld.5 . . . . . . . 8 (𝜑𝐺 ∈ (SubDRing‘𝐿))
12 sdrgsubrg 20924 . . . . . . . 8 (𝐺 ∈ (SubDRing‘𝐿) → 𝐺 ∈ (SubRing‘𝐿))
1311, 12syl 18 . . . . . . 7 (𝜑𝐺 ∈ (SubRing‘𝐿))
14 fldextrspunfld.3 . . . . . . . 8 (𝜑𝐹 ∈ (SubDRing‘𝐼))
15 sdrgsubrg 20924 . . . . . . . 8 (𝐹 ∈ (SubDRing‘𝐼) → 𝐹 ∈ (SubRing‘𝐼))
1614, 15syl 18 . . . . . . 7 (𝜑𝐹 ∈ (SubRing‘𝐼))
17 fldextrspunfld.i . . . . . . . . 9 𝐼 = (𝐿s 𝐺)
1817subsubrg 20727 . . . . . . . 8 (𝐺 ∈ (SubRing‘𝐿) → (𝐹 ∈ (SubRing‘𝐼) ↔ (𝐹 ∈ (SubRing‘𝐿) ∧ 𝐹𝐺)))
1918biimpa 482 . . . . . . 7 ((𝐺 ∈ (SubRing‘𝐿) ∧ 𝐹 ∈ (SubRing‘𝐼)) → (𝐹 ∈ (SubRing‘𝐿) ∧ 𝐹𝐺))
2013, 16, 19syl2anc 596 . . . . . 6 (𝜑 → (𝐹 ∈ (SubRing‘𝐿) ∧ 𝐹𝐺))
2120simpld 500 . . . . 5 (𝜑𝐹 ∈ (SubRing‘𝐿))
22 eqid 2765 . . . . . . . 8 (Base‘𝐽) = (Base‘𝐽)
2322sdrgss 20926 . . . . . . 7 (𝐹 ∈ (SubDRing‘𝐽) → 𝐹 ⊆ (Base‘𝐽))
245, 23syl 18 . . . . . 6 (𝜑𝐹 ⊆ (Base‘𝐽))
25 eqid 2765 . . . . . . . . 9 (Base‘𝐿) = (Base‘𝐿)
2625sdrgss 20926 . . . . . . . 8 (𝐻 ∈ (SubDRing‘𝐿) → 𝐻 ⊆ (Base‘𝐿))
271, 26syl 18 . . . . . . 7 (𝜑𝐻 ⊆ (Base‘𝐿))
282, 25ressbas2 17316 . . . . . . 7 (𝐻 ⊆ (Base‘𝐿) → 𝐻 = (Base‘𝐽))
2927, 28syl 18 . . . . . 6 (𝜑𝐻 = (Base‘𝐽))
3024, 29sseqtrrd 3975 . . . . 5 (𝜑𝐹𝐻)
312subsubrg 20727 . . . . . 6 (𝐻 ∈ (SubRing‘𝐿) → (𝐹 ∈ (SubRing‘𝐽) ↔ (𝐹 ∈ (SubRing‘𝐿) ∧ 𝐹𝐻)))
3231biimpar 483 . . . . 5 ((𝐻 ∈ (SubRing‘𝐿) ∧ (𝐹 ∈ (SubRing‘𝐿) ∧ 𝐹𝐻)) → 𝐹 ∈ (SubRing‘𝐽))
3310, 21, 30, 32syl12anc 850 . . . 4 (𝜑𝐹 ∈ (SubRing‘𝐽))
34 eqid 2765 . . . . 5 ((subringAlg ‘𝐽)‘𝐹) = ((subringAlg ‘𝐽)‘𝐹)
3534, 6sralvec 34015 . . . 4 ((𝐽 ∈ DivRing ∧ (𝐽s 𝐹) ∈ DivRing ∧ 𝐹 ∈ (SubRing‘𝐽)) → ((subringAlg ‘𝐽)‘𝐹) ∈ LVec)
364, 8, 33, 35syl3anc 1398 . . 3 (𝜑 → ((subringAlg ‘𝐽)‘𝐹) ∈ LVec)
37 eqid 2765 . . . 4 (LBasis‘((subringAlg ‘𝐽)‘𝐹)) = (LBasis‘((subringAlg ‘𝐽)‘𝐹))
3837lbsex 21319 . . 3 (((subringAlg ‘𝐽)‘𝐹) ∈ LVec → (LBasis‘((subringAlg ‘𝐽)‘𝐹)) ≠ ∅)
3936, 38syl 18 . 2 (𝜑 → (LBasis‘((subringAlg ‘𝐽)‘𝐹)) ≠ ∅)
40 fldextrspunfld.2 . . . . . . . . . . . 12 (𝜑𝐿 ∈ Field)
41 fldidom 20905 . . . . . . . . . . . 12 (𝐿 ∈ Field → 𝐿 ∈ IDomn)
4240, 41syl 18 . . . . . . . . . . 11 (𝜑𝐿 ∈ IDomn)
4342idomringd 20856 . . . . . . . . . 10 (𝜑𝐿 ∈ Ring)
44 eqidd 2766 . . . . . . . . . 10 (𝜑 → (Base‘𝐿) = (Base‘𝐿))
4525sdrgss 20926 . . . . . . . . . . . 12 (𝐺 ∈ (SubDRing‘𝐿) → 𝐺 ⊆ (Base‘𝐿))
4611, 45syl 18 . . . . . . . . . . 11 (𝜑𝐺 ⊆ (Base‘𝐿))
4746, 27unssd 4145 . . . . . . . . . 10 (𝜑 → (𝐺𝐻) ⊆ (Base‘𝐿))
48 fldextrspunfld.n . . . . . . . . . . 11 𝑁 = (RingSpan‘𝐿)
4948a1i 11 . . . . . . . . . 10 (𝜑𝑁 = (RingSpan‘𝐿))
50 fldextrspunfld.c . . . . . . . . . . 11 𝐶 = (𝑁‘(𝐺𝐻))
5150a1i 11 . . . . . . . . . 10 (𝜑𝐶 = (𝑁‘(𝐺𝐻)))
5243, 44, 47, 49, 51rgspncl 20742 . . . . . . . . 9 (𝜑𝐶 ∈ (SubRing‘𝐿))
5343, 44, 47, 49, 51rgspnssid 20743 . . . . . . . . . 10 (𝜑 → (𝐺𝐻) ⊆ 𝐶)
5453unssad 4146 . . . . . . . . 9 (𝜑𝐺𝐶)
55 fldextrspunfld.e . . . . . . . . . . 11 𝐸 = (𝐿s 𝐶)
5655subsubrg 20727 . . . . . . . . . 10 (𝐶 ∈ (SubRing‘𝐿) → (𝐺 ∈ (SubRing‘𝐸) ↔ (𝐺 ∈ (SubRing‘𝐿) ∧ 𝐺𝐶)))
5756biimpar 483 . . . . . . . . 9 ((𝐶 ∈ (SubRing‘𝐿) ∧ (𝐺 ∈ (SubRing‘𝐿) ∧ 𝐺𝐶)) → 𝐺 ∈ (SubRing‘𝐸))
5852, 13, 54, 57syl12anc 850 . . . . . . . 8 (𝜑𝐺 ∈ (SubRing‘𝐸))
59 eqid 2765 . . . . . . . . 9 ((subringAlg ‘𝐸)‘𝐺) = ((subringAlg ‘𝐸)‘𝐺)
6059sralmod 21338 . . . . . . . 8 (𝐺 ∈ (SubRing‘𝐸) → ((subringAlg ‘𝐸)‘𝐺) ∈ LMod)
6158, 60syl 18 . . . . . . 7 (𝜑 → ((subringAlg ‘𝐸)‘𝐺) ∈ LMod)
62 ressabs 17326 . . . . . . . . . . 11 ((𝐶 ∈ (SubRing‘𝐿) ∧ 𝐺𝐶) → ((𝐿s 𝐶) ↾s 𝐺) = (𝐿s 𝐺))
6352, 54, 62syl2anc 596 . . . . . . . . . 10 (𝜑 → ((𝐿s 𝐶) ↾s 𝐺) = (𝐿s 𝐺))
6455oveq1i 7426 . . . . . . . . . 10 (𝐸s 𝐺) = ((𝐿s 𝐶) ↾s 𝐺)
6563, 64, 173eqtr4g 2825 . . . . . . . . 9 (𝜑 → (𝐸s 𝐺) = 𝐼)
66 eqidd 2766 . . . . . . . . . 10 (𝜑 → ((subringAlg ‘𝐸)‘𝐺) = ((subringAlg ‘𝐸)‘𝐺))
6725subrgss 20701 . . . . . . . . . . . . . 14 (𝐶 ∈ (SubRing‘𝐿) → 𝐶 ⊆ (Base‘𝐿))
6852, 67syl 18 . . . . . . . . . . . . 13 (𝜑𝐶 ⊆ (Base‘𝐿))
6955, 25ressbas2 17316 . . . . . . . . . . . . 13 (𝐶 ⊆ (Base‘𝐿) → 𝐶 = (Base‘𝐸))
7068, 69syl 18 . . . . . . . . . . . 12 (𝜑𝐶 = (Base‘𝐸))
7153, 70sseqtrd 3974 . . . . . . . . . . 11 (𝜑 → (𝐺𝐻) ⊆ (Base‘𝐸))
7271unssad 4146 . . . . . . . . . 10 (𝜑𝐺 ⊆ (Base‘𝐸))
7366, 72srasca 21331 . . . . . . . . 9 (𝜑 → (𝐸s 𝐺) = (Scalar‘((subringAlg ‘𝐸)‘𝐺)))
7465, 73eqtr3d 2802 . . . . . . . 8 (𝜑𝐼 = (Scalar‘((subringAlg ‘𝐸)‘𝐺)))
7517sdrgdrng 20923 . . . . . . . . 9 (𝐺 ∈ (SubDRing‘𝐿) → 𝐼 ∈ DivRing)
7611, 75syl 18 . . . . . . . 8 (𝜑𝐼 ∈ DivRing)
7774, 76eqeltrrd 2866 . . . . . . 7 (𝜑 → (Scalar‘((subringAlg ‘𝐸)‘𝐺)) ∈ DivRing)
78 eqid 2765 . . . . . . . 8 (Scalar‘((subringAlg ‘𝐸)‘𝐺)) = (Scalar‘((subringAlg ‘𝐸)‘𝐺))
7978islvec 21255 . . . . . . 7 (((subringAlg ‘𝐸)‘𝐺) ∈ LVec ↔ (((subringAlg ‘𝐸)‘𝐺) ∈ LMod ∧ (Scalar‘((subringAlg ‘𝐸)‘𝐺)) ∈ DivRing))
8061, 77, 79sylanbrc 595 . . . . . 6 (𝜑 → ((subringAlg ‘𝐸)‘𝐺) ∈ LVec)
81 eqid 2765 . . . . . . 7 (LBasis‘((subringAlg ‘𝐸)‘𝐺)) = (LBasis‘((subringAlg ‘𝐸)‘𝐺))
8281lbsex 21319 . . . . . 6 (((subringAlg ‘𝐸)‘𝐺) ∈ LVec → (LBasis‘((subringAlg ‘𝐸)‘𝐺)) ≠ ∅)
8380, 82syl 18 . . . . 5 (𝜑 → (LBasis‘((subringAlg ‘𝐸)‘𝐺)) ≠ ∅)
8483adantr 486 . . . 4 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (LBasis‘((subringAlg ‘𝐸)‘𝐺)) ≠ ∅)
8580ad2antrr 739 . . . . . 6 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → ((subringAlg ‘𝐸)‘𝐺) ∈ LVec)
86 simpr 490 . . . . . 6 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺)))
8781dimval 34031 . . . . . 6 ((((subringAlg ‘𝐸)‘𝐺) ∈ LVec ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → (dim‘((subringAlg ‘𝐸)‘𝐺)) = (♯‘𝑐))
8885, 86, 87syl2anc 596 . . . . 5 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → (dim‘((subringAlg ‘𝐸)‘𝐺)) = (♯‘𝑐))
89 eqid 2765 . . . . . 6 (Base‘((subringAlg ‘𝐸)‘𝐺)) = (Base‘((subringAlg ‘𝐸)‘𝐺))
90 eqid 2765 . . . . . 6 (LSpan‘((subringAlg ‘𝐸)‘𝐺)) = (LSpan‘((subringAlg ‘𝐸)‘𝐺))
91 eqid 2765 . . . . . . . . . . . 12 (Base‘((subringAlg ‘𝐽)‘𝐹)) = (Base‘((subringAlg ‘𝐽)‘𝐹))
9291, 37lbsss 21228 . . . . . . . . . . 11 (𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹)) → 𝑏 ⊆ (Base‘((subringAlg ‘𝐽)‘𝐹)))
9392ad2antlr 740 . . . . . . . . . 10 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝑏 ⊆ (Base‘((subringAlg ‘𝐽)‘𝐹)))
94 eqidd 2766 . . . . . . . . . . . . 13 (𝜑 → ((subringAlg ‘𝐽)‘𝐹) = ((subringAlg ‘𝐽)‘𝐹))
9594, 24srabase 21328 . . . . . . . . . . . 12 (𝜑 → (Base‘𝐽) = (Base‘((subringAlg ‘𝐽)‘𝐹)))
9629, 95eqtrd 2800 . . . . . . . . . . 11 (𝜑𝐻 = (Base‘((subringAlg ‘𝐽)‘𝐹)))
9796ad2antrr 739 . . . . . . . . . 10 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝐻 = (Base‘((subringAlg ‘𝐽)‘𝐹)))
9893, 97sseqtrrd 3975 . . . . . . . . 9 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝑏𝐻)
9953unssbd 4147 . . . . . . . . . 10 (𝜑𝐻𝐶)
10099ad2antrr 739 . . . . . . . . 9 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝐻𝐶)
10198, 100sstrd 3948 . . . . . . . 8 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝑏𝐶)
10270ad2antrr 739 . . . . . . . 8 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝐶 = (Base‘𝐸))
103101, 102sseqtrd 3974 . . . . . . 7 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝑏 ⊆ (Base‘𝐸))
104 eqidd 2766 . . . . . . . 8 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → ((subringAlg ‘𝐸)‘𝐺) = ((subringAlg ‘𝐸)‘𝐺))
10572ad2antrr 739 . . . . . . . 8 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝐺 ⊆ (Base‘𝐸))
106104, 105srabase 21328 . . . . . . 7 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → (Base‘𝐸) = (Base‘((subringAlg ‘𝐸)‘𝐺)))
107103, 106sseqtrd 3974 . . . . . 6 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝑏 ⊆ (Base‘((subringAlg ‘𝐸)‘𝐺)))
10861ad2antrr 739 . . . . . . . 8 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → ((subringAlg ‘𝐸)‘𝐺) ∈ LMod)
10989, 90lspssv 21134 . . . . . . . 8 ((((subringAlg ‘𝐸)‘𝐺) ∈ LMod ∧ 𝑏 ⊆ (Base‘((subringAlg ‘𝐸)‘𝐺))) → ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏) ⊆ (Base‘((subringAlg ‘𝐸)‘𝐺)))
110108, 107, 109syl2anc 596 . . . . . . 7 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏) ⊆ (Base‘((subringAlg ‘𝐸)‘𝐺)))
111 fldextrspunfld.k . . . . . . . . . . . . 13 𝐾 = (𝐿s 𝐹)
11240adantr 486 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐿 ∈ Field)
11314adantr 486 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐹 ∈ (SubDRing‘𝐼))
1145adantr 486 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐹 ∈ (SubDRing‘𝐽))
11511adantr 486 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐺 ∈ (SubDRing‘𝐿))
1161adantr 486 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐻 ∈ (SubDRing‘𝐿))
117 simpr 490 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹)))
118 fldsdrgfld 20931 . . . . . . . . . . . . . . . . . . . . 21 ((𝐿 ∈ Field ∧ 𝐻 ∈ (SubDRing‘𝐿)) → (𝐿s 𝐻) ∈ Field)
11940, 1, 118syl2anc 596 . . . . . . . . . . . . . . . . . . . 20 (𝜑 → (𝐿s 𝐻) ∈ Field)
1202, 119eqeltrid 2869 . . . . . . . . . . . . . . . . . . 19 (𝜑𝐽 ∈ Field)
121 ressabs 17326 . . . . . . . . . . . . . . . . . . . . . 22 ((𝐻 ∈ (SubDRing‘𝐿) ∧ 𝐹𝐻) → ((𝐿s 𝐻) ↾s 𝐹) = (𝐿s 𝐹))
1221, 30, 121syl2anc 596 . . . . . . . . . . . . . . . . . . . . 21 (𝜑 → ((𝐿s 𝐻) ↾s 𝐹) = (𝐿s 𝐹))
1232oveq1i 7426 . . . . . . . . . . . . . . . . . . . . 21 (𝐽s 𝐹) = ((𝐿s 𝐻) ↾s 𝐹)
124122, 123, 1113eqtr4g 2825 . . . . . . . . . . . . . . . . . . . 20 (𝜑 → (𝐽s 𝐹) = 𝐾)
125 fldsdrgfld 20931 . . . . . . . . . . . . . . . . . . . . 21 ((𝐽 ∈ Field ∧ 𝐹 ∈ (SubDRing‘𝐽)) → (𝐽s 𝐹) ∈ Field)
126120, 5, 125syl2anc 596 . . . . . . . . . . . . . . . . . . . 20 (𝜑 → (𝐽s 𝐹) ∈ Field)
127124, 126eqeltrrd 2866 . . . . . . . . . . . . . . . . . . 19 (𝜑𝐾 ∈ Field)
12830, 27sstrd 3948 . . . . . . . . . . . . . . . . . . . . . 22 (𝜑𝐹 ⊆ (Base‘𝐿))
129111, 25ressbas2 17316 . . . . . . . . . . . . . . . . . . . . . 22 (𝐹 ⊆ (Base‘𝐿) → 𝐹 = (Base‘𝐾))
130128, 129syl 18 . . . . . . . . . . . . . . . . . . . . 21 (𝜑𝐹 = (Base‘𝐾))
131130oveq2d 7432 . . . . . . . . . . . . . . . . . . . 20 (𝜑 → (𝐽s 𝐹) = (𝐽s (Base‘𝐾)))
132124, 131eqtr3d 2802 . . . . . . . . . . . . . . . . . . 19 (𝜑𝐾 = (𝐽s (Base‘𝐾)))
133130, 33eqeltrrd 2866 . . . . . . . . . . . . . . . . . . 19 (𝜑 → (Base‘𝐾) ∈ (SubRing‘𝐽))
134 brfldext 34075 . . . . . . . . . . . . . . . . . . . 20 ((𝐽 ∈ Field ∧ 𝐾 ∈ Field) → (𝐽/FldExt𝐾 ↔ (𝐾 = (𝐽s (Base‘𝐾)) ∧ (Base‘𝐾) ∈ (SubRing‘𝐽))))
135134biimpar 483 . . . . . . . . . . . . . . . . . . 19 (((𝐽 ∈ Field ∧ 𝐾 ∈ Field) ∧ (𝐾 = (𝐽s (Base‘𝐾)) ∧ (Base‘𝐾) ∈ (SubRing‘𝐽))) → 𝐽/FldExt𝐾)
136120, 127, 132, 133, 135syl22anc 852 . . . . . . . . . . . . . . . . . 18 (𝜑𝐽/FldExt𝐾)
137136adantr 486 . . . . . . . . . . . . . . . . 17 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐽/FldExt𝐾)
138 extdgval 34083 . . . . . . . . . . . . . . . . 17 (𝐽/FldExt𝐾 → (𝐽[:]𝐾) = (dim‘((subringAlg ‘𝐽)‘(Base‘𝐾))))
139137, 138syl 18 . . . . . . . . . . . . . . . 16 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (𝐽[:]𝐾) = (dim‘((subringAlg ‘𝐽)‘(Base‘𝐾))))
140130fveq2d 6889 . . . . . . . . . . . . . . . . . 18 (𝜑 → ((subringAlg ‘𝐽)‘𝐹) = ((subringAlg ‘𝐽)‘(Base‘𝐾)))
141140fveq2d 6889 . . . . . . . . . . . . . . . . 17 (𝜑 → (dim‘((subringAlg ‘𝐽)‘𝐹)) = (dim‘((subringAlg ‘𝐽)‘(Base‘𝐾))))
142141adantr 486 . . . . . . . . . . . . . . . 16 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (dim‘((subringAlg ‘𝐽)‘𝐹)) = (dim‘((subringAlg ‘𝐽)‘(Base‘𝐾))))
14337dimval 34031 . . . . . . . . . . . . . . . . 17 ((((subringAlg ‘𝐽)‘𝐹) ∈ LVec ∧ 𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (dim‘((subringAlg ‘𝐽)‘𝐹)) = (♯‘𝑏))
14436, 143sylan 592 . . . . . . . . . . . . . . . 16 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (dim‘((subringAlg ‘𝐽)‘𝐹)) = (♯‘𝑏))
145139, 142, 1443eqtr2d 2806 . . . . . . . . . . . . . . 15 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (𝐽[:]𝐾) = (♯‘𝑏))
146 fldextrspunfld.7 . . . . . . . . . . . . . . . 16 (𝜑 → (𝐽[:]𝐾) ∈ ℕ0)
147146adantr 486 . . . . . . . . . . . . . . 15 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (𝐽[:]𝐾) ∈ ℕ0)
148145, 147eqeltrrd 2866 . . . . . . . . . . . . . 14 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (♯‘𝑏) ∈ ℕ0)
149 hashclb 14408 . . . . . . . . . . . . . . 15 (𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹)) → (𝑏 ∈ Fin ↔ (♯‘𝑏) ∈ ℕ0))
150149biimpar 483 . . . . . . . . . . . . . 14 ((𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹)) ∧ (♯‘𝑏) ∈ ℕ0) → 𝑏 ∈ Fin)
151117, 148, 150syl2anc 596 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝑏 ∈ Fin)
152111, 17, 2, 112, 113, 114, 115, 116, 48, 50, 55, 117, 151fldextrspunlsp 34104 . . . . . . . . . . . 12 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐶 = ((LSpan‘((subringAlg ‘𝐿)‘𝐺))‘𝑏))
153152eqimssd 3994 . . . . . . . . . . 11 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐶 ⊆ ((LSpan‘((subringAlg ‘𝐿)‘𝐺))‘𝑏))
15425, 55, 68, 54, 40resssra 34017 . . . . . . . . . . . . . . 15 (𝜑 → ((subringAlg ‘𝐸)‘𝐺) = (((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶))
155154fveq2d 6889 . . . . . . . . . . . . . 14 (𝜑 → (LSpan‘((subringAlg ‘𝐸)‘𝐺)) = (LSpan‘(((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶)))
156155adantr 486 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (LSpan‘((subringAlg ‘𝐸)‘𝐺)) = (LSpan‘(((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶)))
157156fveq1d 6887 . . . . . . . . . . . 12 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏) = ((LSpan‘(((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶))‘𝑏))
158115, 12syl 18 . . . . . . . . . . . . . 14 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐺 ∈ (SubRing‘𝐿))
159 eqid 2765 . . . . . . . . . . . . . . 15 ((subringAlg ‘𝐿)‘𝐺) = ((subringAlg ‘𝐿)‘𝐺)
160159sralmod 21338 . . . . . . . . . . . . . 14 (𝐺 ∈ (SubRing‘𝐿) → ((subringAlg ‘𝐿)‘𝐺) ∈ LMod)
161158, 160syl 18 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → ((subringAlg ‘𝐿)‘𝐺) ∈ LMod)
162117, 92syl 18 . . . . . . . . . . . . . . . . . 18 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝑏 ⊆ (Base‘((subringAlg ‘𝐽)‘𝐹)))
16396adantr 486 . . . . . . . . . . . . . . . . . 18 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐻 = (Base‘((subringAlg ‘𝐽)‘𝐹)))
164162, 163sseqtrrd 3975 . . . . . . . . . . . . . . . . 17 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝑏𝐻)
165116, 26syl 18 . . . . . . . . . . . . . . . . 17 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐻 ⊆ (Base‘𝐿))
166164, 165sstrd 3948 . . . . . . . . . . . . . . . 16 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝑏 ⊆ (Base‘𝐿))
167 eqidd 2766 . . . . . . . . . . . . . . . . . 18 (𝜑 → ((subringAlg ‘𝐿)‘𝐺) = ((subringAlg ‘𝐿)‘𝐺))
168167, 46srabase 21328 . . . . . . . . . . . . . . . . 17 (𝜑 → (Base‘𝐿) = (Base‘((subringAlg ‘𝐿)‘𝐺)))
169168adantr 486 . . . . . . . . . . . . . . . 16 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (Base‘𝐿) = (Base‘((subringAlg ‘𝐿)‘𝐺)))
170166, 169sseqtrd 3974 . . . . . . . . . . . . . . 15 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝑏 ⊆ (Base‘((subringAlg ‘𝐿)‘𝐺)))
171 eqid 2765 . . . . . . . . . . . . . . . 16 (Base‘((subringAlg ‘𝐿)‘𝐺)) = (Base‘((subringAlg ‘𝐿)‘𝐺))
172 eqid 2765 . . . . . . . . . . . . . . . 16 (LSubSp‘((subringAlg ‘𝐿)‘𝐺)) = (LSubSp‘((subringAlg ‘𝐿)‘𝐺))
173 eqid 2765 . . . . . . . . . . . . . . . 16 (LSpan‘((subringAlg ‘𝐿)‘𝐺)) = (LSpan‘((subringAlg ‘𝐿)‘𝐺))
174171, 172, 173lspcl 21127 . . . . . . . . . . . . . . 15 ((((subringAlg ‘𝐿)‘𝐺) ∈ LMod ∧ 𝑏 ⊆ (Base‘((subringAlg ‘𝐿)‘𝐺))) → ((LSpan‘((subringAlg ‘𝐿)‘𝐺))‘𝑏) ∈ (LSubSp‘((subringAlg ‘𝐿)‘𝐺)))
175161, 170, 174syl2anc 596 . . . . . . . . . . . . . 14 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → ((LSpan‘((subringAlg ‘𝐿)‘𝐺))‘𝑏) ∈ (LSubSp‘((subringAlg ‘𝐿)‘𝐺)))
176152, 175eqeltrd 2865 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐶 ∈ (LSubSp‘((subringAlg ‘𝐿)‘𝐺)))
17799adantr 486 . . . . . . . . . . . . . 14 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐻𝐶)
178164, 177sstrd 3948 . . . . . . . . . . . . 13 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝑏𝐶)
179 eqid 2765 . . . . . . . . . . . . . 14 (((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶) = (((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶)
180 eqid 2765 . . . . . . . . . . . . . 14 (LSpan‘(((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶)) = (LSpan‘(((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶))
181179, 173, 180, 172lsslsp 21166 . . . . . . . . . . . . 13 ((((subringAlg ‘𝐿)‘𝐺) ∈ LMod ∧ 𝐶 ∈ (LSubSp‘((subringAlg ‘𝐿)‘𝐺)) ∧ 𝑏𝐶) → ((LSpan‘(((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶))‘𝑏) = ((LSpan‘((subringAlg ‘𝐿)‘𝐺))‘𝑏))
182161, 176, 178, 181syl3anc 1398 . . . . . . . . . . . 12 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → ((LSpan‘(((subringAlg ‘𝐿)‘𝐺) ↾s 𝐶))‘𝑏) = ((LSpan‘((subringAlg ‘𝐿)‘𝐺))‘𝑏))
183157, 182eqtr2d 2801 . . . . . . . . . . 11 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → ((LSpan‘((subringAlg ‘𝐿)‘𝐺))‘𝑏) = ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏))
184153, 183sseqtrd 3974 . . . . . . . . . 10 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → 𝐶 ⊆ ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏))
185184adantr 486 . . . . . . . . 9 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → 𝐶 ⊆ ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏))
186102, 185eqsstrrd 3973 . . . . . . . 8 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → (Base‘𝐸) ⊆ ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏))
187106, 186eqsstrrd 3973 . . . . . . 7 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → (Base‘((subringAlg ‘𝐸)‘𝐺)) ⊆ ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏))
188110, 187eqssd 3955 . . . . . 6 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → ((LSpan‘((subringAlg ‘𝐸)‘𝐺))‘𝑏) = (Base‘((subringAlg ‘𝐸)‘𝐺)))
18989, 81, 90, 85, 86, 107, 188lbslelsp 34028 . . . . 5 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → (♯‘𝑐) ≤ (♯‘𝑏))
19088, 189eqbrtrd 5135 . . . 4 (((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) ∧ 𝑐 ∈ (LBasis‘((subringAlg ‘𝐸)‘𝐺))) → (dim‘((subringAlg ‘𝐸)‘𝐺)) ≤ (♯‘𝑏))
19184, 190n0limd 4308 . . 3 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (dim‘((subringAlg ‘𝐸)‘𝐺)) ≤ (♯‘𝑏))
192191, 145breqtrrd 5141 . 2 ((𝜑𝑏 ∈ (LBasis‘((subringAlg ‘𝐽)‘𝐹))) → (dim‘((subringAlg ‘𝐸)‘𝐺)) ≤ (𝐽[:]𝐾))
19339, 192n0limd 4308 1 (𝜑 → (dim‘((subringAlg ‘𝐸)‘𝐺)) ≤ (𝐽[:]𝐾))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  wi 4  wa 401   = wceq 1570  wcel 2146  wne 2960  cun 3904  wss 3906  c0 4286   class class class wbr 5111  cfv 6540  (class class class)co 7416  Fincfn 8945  cle 11255  0cn0 12515  chash 14380  Basecbs 17287  s cress 17308  Scalarcsca 17331  SubRingcsubrg 20698  RingSpancrgspn 20739  IDomncidom 20822  DivRingcdr 20857  Fieldcfield 20858  SubDRingcsdrg 20919  LModclmod 21011  LSubSpclss 21082  LSpanclspn 21122  LBasisclbs 21225  LVecclvec 21253  subringAlg csra 21322  dimcldim 34029  /FldExtcfldext 34068  [:]cextdg 34070
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 2148  ax-9 2156  ax-10 2179  ax-11 2195  ax-12 2216  ax-ext 2737  ax-rep 5240  ax-sep 5259  ax-nul 5271  ax-pow 5338  ax-pr 5406  ax-un 7738  ax-reg 9557  ax-inf2 9613  ax-ac2 10458  ax-cnex 11167  ax-resscn 11168  ax-1cn 11169  ax-icn 11170  ax-addcl 11171  ax-addrcl 11172  ax-mulcl 11173  ax-mulrcl 11174  ax-mulcom 11175  ax-addass 11176  ax-mulass 11177  ax-distr 11178  ax-i2m1 11179  ax-1ne0 11180  ax-1rid 11181  ax-rnegex 11182  ax-rrecex 11183  ax-cnre 11184  ax-pre-lttri 11185  ax-pre-lttrn 11186  ax-pre-ltadd 11187  ax-pre-mulgt0 11188  ax-pre-sup 11189  ax-addf 11190
This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2569  df-eu 2599  df-clab 2744  df-cleq 2757  df-clel 2840  df-nfc 2914  df-ne 2961  df-nel 3067  df-ral 3082  df-rex 3092  df-rmo 3371  df-reu 3372  df-rab 3419  df-v 3459  df-sbc 3747  df-csb 3855  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-pss 3926  df-nul 4287  df-if 4490  df-pw 4566  df-sn 4592  df-pr 4594  df-tp 4596  df-op 4598  df-uni 4875  df-int 4915  df-iun 4960  df-iin 4961  df-br 5112  df-opab 5176  df-mpt 5195  df-tr 5221  df-id 5558  df-eprel 5563  df-po 5571  df-so 5572  df-fr 5616  df-se 5617  df-we 5618  df-xp 5669  df-rel 5670  df-cnv 5671  df-co 5672  df-dm 5673  df-rn 5674  df-res 5675  df-ima 5676  df-pred 6306  df-ord 6367  df-on 6368  df-lim 6369  df-suc 6370  df-iota 6496  df-fun 6542  df-fn 6543  df-f 6544  df-f1 6545  df-fo 6546  df-f1o 6547  df-fv 6548  df-isom 6549  df-riota 7373  df-ov 7419  df-oprab 7420  df-mpo 7421  df-of 7680  df-rpss 7726  df-om 7865  df-1st 7988  df-2nd 7989  df-supp 8159  df-tpos 8224  df-frecs 8280  df-wrecs 8311  df-recs 8360  df-rdg 8399  df-1o 8455  df-2o 8456  df-oadd 8459  df-er 8696  df-map 8828  df-ixp 8898  df-en 8946  df-dom 8947  df-sdom 8948  df-fin 8949  df-fsupp 9325  df-sup 9405  df-inf 9406  df-oi 9475  df-r1 9739  df-rank 9740  df-scott 9861  df-dju 9899  df-card 9937  df-acn 9940  df-ac 10112  df-pnf 11256  df-mnf 11257  df-xr 11258  df-ltxr 11259  df-le 11260  df-sub 11454  df-neg 11455  df-div 11883  df-ind 12230  df-nn 12245  df-2 12314  df-3 12315  df-4 12316  df-5 12317  df-6 12318  df-7 12319  df-8 12320  df-9 12321  df-n0 12516  df-xnn0 12589  df-z 12603  df-dec 12724  df-uz 12875  df-rp 13029  df-fz 13548  df-fzo 13696  df-seq 14052  df-exp 14112  df-hash 14381  df-word 14565  df-lsw 14614  df-concat 14622  df-s1 14649  df-substr 14695  df-pfx 14727  df-s2 14905  df-cj 15170  df-re 15171  df-im 15172  df-sqrt 15306  df-abs 15307  df-clim 15559  df-sum 15758  df-struct 17225  df-sets 17242  df-slot 17260  df-ndx 17272  df-base 17288  df-ress 17309  df-plusg 17341  df-mulr 17342  df-starv 17343  df-sca 17344  df-vsca 17345  df-ip 17346  df-tset 17347  df-ple 17348  df-ocomp 17349  df-ds 17350  df-unif 17351  df-hom 17352  df-cco 17353  df-0g 17512  df-gsum 17513  df-prds 17518  df-pws 17520  df-mre 17656  df-mrc 17657  df-mri 17658  df-acs 17659  df-proset 18368  df-drs 18369  df-poset 18387  df-ipo 18602  df-mgm 18716  df-sgrp 18799  df-mnd 18815  df-mhm 18865  df-submnd 18866  df-grp 19027  df-minusg 19028  df-sbg 19029  df-mulg 19158  df-subg 19213  df-ghm 19308  df-cntz 19411  df-cmn 19876  df-abl 19877  df-mgp 20241  df-rng 20255  df-ur 20288  df-ring 20341  df-cring 20342  df-oppr 20445  df-dvdsr 20465  df-unit 20466  df-invr 20496  df-nzr 20640  df-subrng 20675  df-subrg 20699  df-rgspn 20740  df-rlreg 20823  df-domn 20824  df-idom 20825  df-drng 20859  df-field 20860  df-sdrg 20920  df-lmod 21013  df-lss 21083  df-lsp 21123  df-lmhm 21173  df-lbs 21226  df-lvec 21254  df-sra 21324  df-rgmod 21325  df-cnfld 21553  df-zring 21627  df-dsmm 21912  df-frlm 21927  df-uvc 21963  df-dim 34030  df-fldext 34071  df-extdg 34072
This theorem is used by:  fldextrspunfld  34106  fldextrspundgle  34108
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