Theorem ismgmOLD 38893

Description: Obsolete version of ismgm 18826 as of 3-Feb-2020. The predicate "is a magma". (Contributed by FL, 2-Nov-2009.) (New usage is discouraged.) (Proof modification is discouraged.)

Hypothesis

Ref	Expression
ismgmOLD.1	⊢ 𝑋 = dom dom 𝐺

Assertion

Ref	Expression
ismgmOLD	⊢ (𝐺 ∈ 𝐴 → (𝐺 ∈ Magma ↔ 𝐺:(𝑋 × 𝑋)⟶𝑋))

Proof of Theorem ismgmOLD

Dummy variables 𝑔 𝑡 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		feq1 6692	. . . . 5 ⊢ (𝑔 = 𝐺 → (𝑔:(𝑡 × 𝑡)⟶𝑡 ↔ 𝐺:(𝑡 × 𝑡)⟶𝑡))
2	1	exbidv 1953	. . . 4 ⊢ (𝑔 = 𝐺 → (∃𝑡 𝑔:(𝑡 × 𝑡)⟶𝑡 ↔ ∃𝑡 𝐺:(𝑡 × 𝑡)⟶𝑡))
3		df-mgmOLD 38892	. . . 4 ⊢ Magma = {𝑔 ∣ ∃𝑡 𝑔:(𝑡 × 𝑡)⟶𝑡}
4	2, 3	elab2g 3633	. . 3 ⊢ (𝐺 ∈ 𝐴 → (𝐺 ∈ Magma ↔ ∃𝑡 𝐺:(𝑡 × 𝑡)⟶𝑡))
5		f00 6769	. . . . . . . 8 ⊢ (𝐺:(∅ × ∅)⟶∅ ↔ (𝐺 = ∅ ∧ (∅ × ∅) = ∅))
6		dmeq 5886	. . . . . . . . . 10 ⊢ (𝐺 = ∅ → dom 𝐺 = dom ∅)
7		dmeq 5886	. . . . . . . . . . 11 ⊢ (dom 𝐺 = dom ∅ → dom dom 𝐺 = dom dom ∅)
8		dm0 5903	. . . . . . . . . . . . 13 ⊢ dom ∅ = ∅
9	8	dmeqi 5887	. . . . . . . . . . . 12 ⊢ dom dom ∅ = dom ∅
10	9, 8	eqtri 2783	. . . . . . . . . . 11 ⊢ dom dom ∅ = ∅
11	7, 10	eqtr2di 2812	. . . . . . . . . 10 ⊢ (dom 𝐺 = dom ∅ → ∅ = dom dom 𝐺)
12	6, 11	syl 18	. . . . . . . . 9 ⊢ (𝐺 = ∅ → ∅ = dom dom 𝐺)
13	12	adantr 486	. . . . . . . 8 ⊢ ((𝐺 = ∅ ∧ (∅ × ∅) = ∅) → ∅ = dom dom 𝐺)
14	5, 13	sylbi 220	. . . . . . 7 ⊢ (𝐺:(∅ × ∅)⟶∅ → ∅ = dom dom 𝐺)
15		xpeq12 5676	. . . . . . . . . 10 ⊢ ((𝑡 = ∅ ∧ 𝑡 = ∅) → (𝑡 × 𝑡) = (∅ × ∅))
16	15	anidms 577	. . . . . . . . 9 ⊢ (𝑡 = ∅ → (𝑡 × 𝑡) = (∅ × ∅))
17		feq23 6695	. . . . . . . . 9 ⊢ (((𝑡 × 𝑡) = (∅ × ∅) ∧ 𝑡 = ∅) → (𝐺:(𝑡 × 𝑡)⟶𝑡 ↔ 𝐺:(∅ × ∅)⟶∅))
18	16, 17	mpancom 701	. . . . . . . 8 ⊢ (𝑡 = ∅ → (𝐺:(𝑡 × 𝑡)⟶𝑡 ↔ 𝐺:(∅ × ∅)⟶∅))
19		eqeq1 2764	. . . . . . . 8 ⊢ (𝑡 = ∅ → (𝑡 = dom dom 𝐺 ↔ ∅ = dom dom 𝐺))
20	18, 19	imbi12d 347	. . . . . . 7 ⊢ (𝑡 = ∅ → ((𝐺:(𝑡 × 𝑡)⟶𝑡 → 𝑡 = dom dom 𝐺) ↔ (𝐺:(∅ × ∅)⟶∅ → ∅ = dom dom 𝐺)))
21	14, 20	mpbiri 261	. . . . . 6 ⊢ (𝑡 = ∅ → (𝐺:(𝑡 × 𝑡)⟶𝑡 → 𝑡 = dom dom 𝐺))
22		fdm 6724	. . . . . . . 8 ⊢ (𝐺:(𝑡 × 𝑡)⟶𝑡 → dom 𝐺 = (𝑡 × 𝑡))
23		dmeq 5886	. . . . . . . 8 ⊢ (dom 𝐺 = (𝑡 × 𝑡) → dom dom 𝐺 = dom (𝑡 × 𝑡))
24		df-ne 2956	. . . . . . . . . . . 12 ⊢ (𝑡 ≠ ∅ ↔ ¬ 𝑡 = ∅)
25		dmxp 5912	. . . . . . . . . . . 12 ⊢ (𝑡 ≠ ∅ → dom (𝑡 × 𝑡) = 𝑡)
26	24, 25	sylbir 238	. . . . . . . . . . 11 ⊢ (¬ 𝑡 = ∅ → dom (𝑡 × 𝑡) = 𝑡)
27	26	eqeq1d 2762	. . . . . . . . . 10 ⊢ (¬ 𝑡 = ∅ → (dom (𝑡 × 𝑡) = dom dom 𝐺 ↔ 𝑡 = dom dom 𝐺))
28	27	biimpcd 252	. . . . . . . . 9 ⊢ (dom (𝑡 × 𝑡) = dom dom 𝐺 → (¬ 𝑡 = ∅ → 𝑡 = dom dom 𝐺))
29	28	eqcoms 2768	. . . . . . . 8 ⊢ (dom dom 𝐺 = dom (𝑡 × 𝑡) → (¬ 𝑡 = ∅ → 𝑡 = dom dom 𝐺))
30	22, 23, 29	3syl 19	. . . . . . 7 ⊢ (𝐺:(𝑡 × 𝑡)⟶𝑡 → (¬ 𝑡 = ∅ → 𝑡 = dom dom 𝐺))
31	30	com12 33	. . . . . 6 ⊢ (¬ 𝑡 = ∅ → (𝐺:(𝑡 × 𝑡)⟶𝑡 → 𝑡 = dom dom 𝐺))
32	21, 31	pm2.61i 184	. . . . 5 ⊢ (𝐺:(𝑡 × 𝑡)⟶𝑡 → 𝑡 = dom dom 𝐺)
33	32	pm4.71ri 570	. . . 4 ⊢ (𝐺:(𝑡 × 𝑡)⟶𝑡 ↔ (𝑡 = dom dom 𝐺 ∧ 𝐺:(𝑡 × 𝑡)⟶𝑡))
34	33	exbii 1880	. . 3 ⊢ (∃𝑡 𝐺:(𝑡 × 𝑡)⟶𝑡 ↔ ∃𝑡(𝑡 = dom dom 𝐺 ∧ 𝐺:(𝑡 × 𝑡)⟶𝑡))
35	4, 34	bitrdi 290	. 2 ⊢ (𝐺 ∈ 𝐴 → (𝐺 ∈ Magma ↔ ∃𝑡(𝑡 = dom dom 𝐺 ∧ 𝐺:(𝑡 × 𝑡)⟶𝑡)))
36		dmexg 7917	. . 3 ⊢ (𝐺 ∈ 𝐴 → dom 𝐺 ∈ V)
37		dmexg 7917	. . 3 ⊢ (dom 𝐺 ∈ V → dom dom 𝐺 ∈ V)
38		xpeq12 5676	. . . . . . 7 ⊢ ((𝑡 = dom dom 𝐺 ∧ 𝑡 = dom dom 𝐺) → (𝑡 × 𝑡) = (dom dom 𝐺 × dom dom 𝐺))
39	38	anidms 577	. . . . . 6 ⊢ (𝑡 = dom dom 𝐺 → (𝑡 × 𝑡) = (dom dom 𝐺 × dom dom 𝐺))
40		feq23 6695	. . . . . 6 ⊢ (((𝑡 × 𝑡) = (dom dom 𝐺 × dom dom 𝐺) ∧ 𝑡 = dom dom 𝐺) → (𝐺:(𝑡 × 𝑡)⟶𝑡 ↔ 𝐺:(dom dom 𝐺 × dom dom 𝐺)⟶dom dom 𝐺))
41	39, 40	mpancom 701	. . . . 5 ⊢ (𝑡 = dom dom 𝐺 → (𝐺:(𝑡 × 𝑡)⟶𝑡 ↔ 𝐺:(dom dom 𝐺 × dom dom 𝐺)⟶dom dom 𝐺))
42		ismgmOLD.1	. . . . . . . 8 ⊢ 𝑋 = dom dom 𝐺
43	42	eqcomi 2769	. . . . . . 7 ⊢ dom dom 𝐺 = 𝑋
44	43, 43	xpeq12i 5679	. . . . . 6 ⊢ (dom dom 𝐺 × dom dom 𝐺) = (𝑋 × 𝑋)
45	44, 43	feq23i 6708	. . . . 5 ⊢ (𝐺:(dom dom 𝐺 × dom dom 𝐺)⟶dom dom 𝐺 ↔ 𝐺:(𝑋 × 𝑋)⟶𝑋)
46	41, 45	bitrdi 290	. . . 4 ⊢ (𝑡 = dom dom 𝐺 → (𝐺:(𝑡 × 𝑡)⟶𝑡 ↔ 𝐺:(𝑋 × 𝑋)⟶𝑋))
47	46	ceqsexgv 3607	. . 3 ⊢ (dom dom 𝐺 ∈ V → (∃𝑡(𝑡 = dom dom 𝐺 ∧ 𝐺:(𝑡 × 𝑡)⟶𝑡) ↔ 𝐺:(𝑋 × 𝑋)⟶𝑋))
48	36, 37, 47	3syl 19	. 2 ⊢ (𝐺 ∈ 𝐴 → (∃𝑡(𝑡 = dom dom 𝐺 ∧ 𝐺:(𝑡 × 𝑡)⟶𝑡) ↔ 𝐺:(𝑋 × 𝑋)⟶𝑋))
49	35, 48	bitrd 282	1 ⊢ (𝐺 ∈ 𝐴 → (𝐺 ∈ Magma ↔ 𝐺:(𝑋 × 𝑋)⟶𝑋))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1569  ∃wex 1811   ∈ wcel 2144   ≠ wne 2955  Vcvv 3450  ∅c0 4277   × cxp 5649  dom cdm 5651  ⟶wf 6539  Magmacmagm 38891

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-ext 2732  ax-sep 5248  ax-nul 5259  ax-pr 5391  ax-un 7755

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-sb 2099  df-mo 2564  df-clab 2739  df-cleq 2752  df-clel 2835  df-ne 2956  df-ral 3077  df-rex 3087  df-rab 3413  df-v 3452  df-ss 3897  df-dif 4046  df-in 4090  df-un 4150  df-nul 4278  df-if 4482  df-sn 4585  df-pr 4587  df-op 4835  df-uni 4867  df-br 5103  df-opab 5167  df-id 5546  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-rn 5662  df-fun 6545  df-fn 6546  df-f 6547  df-mgmOLD 38892

This theorem is used by:  clmgmOLD  38894  opidonOLD  38895  issmgrpOLD  38906