Theorem odval 17776

Description: Second substitution for the group order definition. (Contributed by Mario Carneiro, 13-Jul-2014.) (Revised by Stefan O'Rear, 5-Sep-2015.) (Revised by AV, 5-Oct-2020.)

Hypotheses

Ref	Expression
odval.1	⊢ 𝑋 = (Base‘𝐺)
odval.2	⊢ · = (.g‘𝐺)
odval.3	⊢ 0 = (0g‘𝐺)
odval.4	⊢ 𝑂 = (od‘𝐺)
odval.i	⊢ 𝐼 = {𝑦 ∈ ℕ ∣ (𝑦 · 𝐴) = 0 }

Assertion

Ref	Expression
odval	⊢ (𝐴 ∈ 𝑋 → (𝑂‘𝐴) = if(𝐼 = ∅, 0, inf(𝐼, ℝ, < )))

Distinct variable groups:   𝑦,𝐴   𝑦,𝐺   𝑦, ·   𝑦, 0

Allowed substitution hints:   𝐼(𝑦)   𝑂(𝑦)   𝑋(𝑦)

Proof of Theorem odval

Dummy variables 𝑖 𝑥 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		oveq2 6557	. . . . . . 7 ⊢ (𝑥 = 𝐴 → (𝑦 · 𝑥) = (𝑦 · 𝐴))
2	1	eqeq1d 2612	. . . . . 6 ⊢ (𝑥 = 𝐴 → ((𝑦 · 𝑥) = 0 ↔ (𝑦 · 𝐴) = 0 ))
3	2	rabbidv 3164	. . . . 5 ⊢ (𝑥 = 𝐴 → {𝑦 ∈ ℕ ∣ (𝑦 · 𝑥) = 0 } = {𝑦 ∈ ℕ ∣ (𝑦 · 𝐴) = 0 })
4		odval.i	. . . . 5 ⊢ 𝐼 = {𝑦 ∈ ℕ ∣ (𝑦 · 𝐴) = 0 }
5	3, 4	syl6eqr 2662	. . . 4 ⊢ (𝑥 = 𝐴 → {𝑦 ∈ ℕ ∣ (𝑦 · 𝑥) = 0 } = 𝐼)
6	5	csbeq1d 3506	. . 3 ⊢ (𝑥 = 𝐴 → ⦋{𝑦 ∈ ℕ ∣ (𝑦 · 𝑥) = 0 } / 𝑖⦌if(𝑖 = ∅, 0, inf(𝑖, ℝ, < )) = ⦋𝐼 / 𝑖⦌if(𝑖 = ∅, 0, inf(𝑖, ℝ, < )))
7		nnex 10903	. . . . 5 ⊢ ℕ ∈ V
8	4, 7	rabex2 4742	. . . 4 ⊢ 𝐼 ∈ V
9		eqeq1 2614	. . . . 5 ⊢ (𝑖 = 𝐼 → (𝑖 = ∅ ↔ 𝐼 = ∅))
10		infeq1 8265	. . . . 5 ⊢ (𝑖 = 𝐼 → inf(𝑖, ℝ, < ) = inf(𝐼, ℝ, < ))
11	9, 10	ifbieq2d 4061	. . . 4 ⊢ (𝑖 = 𝐼 → if(𝑖 = ∅, 0, inf(𝑖, ℝ, < )) = if(𝐼 = ∅, 0, inf(𝐼, ℝ, < )))
12	8, 11	csbie 3525	. . 3 ⊢ ⦋𝐼 / 𝑖⦌if(𝑖 = ∅, 0, inf(𝑖, ℝ, < )) = if(𝐼 = ∅, 0, inf(𝐼, ℝ, < ))
13	6, 12	syl6eq 2660	. 2 ⊢ (𝑥 = 𝐴 → ⦋{𝑦 ∈ ℕ ∣ (𝑦 · 𝑥) = 0 } / 𝑖⦌if(𝑖 = ∅, 0, inf(𝑖, ℝ, < )) = if(𝐼 = ∅, 0, inf(𝐼, ℝ, < )))
14		odval.1	. . 3 ⊢ 𝑋 = (Base‘𝐺)
15		odval.2	. . 3 ⊢ · = (.g‘𝐺)
16		odval.3	. . 3 ⊢ 0 = (0g‘𝐺)
17		odval.4	. . 3 ⊢ 𝑂 = (od‘𝐺)
18	14, 15, 16, 17	odfval 17775	. 2 ⊢ 𝑂 = (𝑥 ∈ 𝑋 ↦ ⦋{𝑦 ∈ ℕ ∣ (𝑦 · 𝑥) = 0 } / 𝑖⦌if(𝑖 = ∅, 0, inf(𝑖, ℝ, < )))
19		c0ex 9913	. . 3 ⊢ 0 ∈ V
20		ltso 9997	. . . 4 ⊢ < Or ℝ
21	20	infex 8282	. . 3 ⊢ inf(𝐼, ℝ, < ) ∈ V
22	19, 21	ifex 4106	. 2 ⊢ if(𝐼 = ∅, 0, inf(𝐼, ℝ, < )) ∈ V
23	13, 18, 22	fvmpt 6191	1 ⊢ (𝐴 ∈ 𝑋 → (𝑂‘𝐴) = if(𝐼 = ∅, 0, inf(𝐼, ℝ, < )))

Syntax hints:   → wi 4   = wceq 1475   ∈ wcel 1977  {crab 2900  ⦋csb 3499  ∅c0 3874  ifcif 4036  ‘cfv 5804  (class class class)co 6549  infcinf 8230  ℝcr 9814  0cc0 9815   < clt 9953  ℕcn 10897  Basecbs 15695  0_gc0g 15923  ._gcmg 17363  odcod 17767

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-rep 4699  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847  ax-cnex 9871  ax-resscn 9872  ax-1cn 9873  ax-icn 9874  ax-addcl 9875  ax-addrcl 9876  ax-mulcl 9877  ax-mulrcl 9878  ax-i2m1 9883  ax-1ne0 9884  ax-rrecex 9887  ax-cnre 9888  ax-pre-lttri 9889  ax-pre-lttrn 9890

This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3or 1032  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-nel 2783  df-ral 2901  df-rex 2902  df-reu 2903  df-rmo 2904  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-pss 3556  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-tp 4130  df-op 4132  df-uni 4373  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-tr 4681  df-eprel 4949  df-id 4953  df-po 4959  df-so 4960  df-fr 4997  df-we 4999  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-pred 5597  df-ord 5643  df-on 5644  df-lim 5645  df-suc 5646  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-ov 6552  df-om 6958  df-wrecs 7294  df-recs 7355  df-rdg 7393  df-er 7629  df-en 7842  df-dom 7843  df-sdom 7844  df-sup 8231  df-inf 8232  df-pnf 9955  df-mnf 9956  df-ltxr 9958  df-nn 10898  df-od 17771

This theorem is referenced by:  odlem1  17777  odlem2  17781  submod  17807  ofldchr  29145