Theorem pwmnd 19123

Description: The power set of a class 𝐴 is a monoid under union. (Contributed by AV, 27-Feb-2024.)

Hypotheses

Ref	Expression
pwmnd.b	⊢ (Base‘𝑀) = 𝒫 𝐴
pwmnd.p	⊢ (+g‘𝑀) = (𝑥 ∈ 𝒫 𝐴, 𝑦 ∈ 𝒫 𝐴 ↦ (𝑥 ∪ 𝑦))

Assertion

Ref	Expression
pwmnd	⊢ 𝑀 ∈ Mnd

Distinct variable group:   𝑥,𝐴,𝑦

Allowed substitution hints:   𝑀(𝑥, 𝑦)

Proof of Theorem pwmnd

Dummy variables 𝑎 𝑏 𝑐 𝑒 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		pwmnd.b	. . . . . 6 ⊢ (Base‘𝑀) = 𝒫 𝐴
2	1	eleq2i 2853	. . . . 5 ⊢ (𝑎 ∈ (Base‘𝑀) ↔ 𝑎 ∈ 𝒫 𝐴)
3	1	eleq2i 2853	. . . . 5 ⊢ (𝑏 ∈ (Base‘𝑀) ↔ 𝑏 ∈ 𝒫 𝐴)
4		pwuncl 7773	. . . . . . 7 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) → (𝑎 ∪ 𝑏) ∈ 𝒫 𝐴)
5		pwmnd.p	. . . . . . . 8 ⊢ (+g‘𝑀) = (𝑥 ∈ 𝒫 𝐴, 𝑦 ∈ 𝒫 𝐴 ↦ (𝑥 ∪ 𝑦))
6	1, 5	pwmndgplus 19121	. . . . . . 7 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)𝑏) = (𝑎 ∪ 𝑏))
7	1	a1i 11	. . . . . . 7 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) → (Base‘𝑀) = 𝒫 𝐴)
8	4, 6, 7	3eltr4d 2876	. . . . . 6 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)𝑏) ∈ (Base‘𝑀))
9	1	eleq2i 2853	. . . . . . . 8 ⊢ (𝑐 ∈ (Base‘𝑀) ↔ 𝑐 ∈ 𝒫 𝐴)
10		unass 4118	. . . . . . . . . 10 ⊢ ((𝑎 ∪ 𝑏) ∪ 𝑐) = (𝑎 ∪ (𝑏 ∪ 𝑐))
11	6	adantr 486	. . . . . . . . . . . 12 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)𝑏) = (𝑎 ∪ 𝑏))
12	11	oveq1d 7427	. . . . . . . . . . 11 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → ((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = ((𝑎 ∪ 𝑏)(+g‘𝑀)𝑐))
13	1, 5	pwmndgplus 19121	. . . . . . . . . . . 12 ⊢ (((𝑎 ∪ 𝑏) ∈ 𝒫 𝐴 ∧ 𝑐 ∈ 𝒫 𝐴) → ((𝑎 ∪ 𝑏)(+g‘𝑀)𝑐) = ((𝑎 ∪ 𝑏) ∪ 𝑐))
14	4, 13	sylan 592	. . . . . . . . . . 11 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → ((𝑎 ∪ 𝑏)(+g‘𝑀)𝑐) = ((𝑎 ∪ 𝑏) ∪ 𝑐))
15	12, 14	eqtrd 2796	. . . . . . . . . 10 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → ((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = ((𝑎 ∪ 𝑏) ∪ 𝑐))
16	1, 5	pwmndgplus 19121	. . . . . . . . . . . . 13 ⊢ ((𝑏 ∈ 𝒫 𝐴 ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑏(+g‘𝑀)𝑐) = (𝑏 ∪ 𝑐))
17	16	adantll 727	. . . . . . . . . . . 12 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑏(+g‘𝑀)𝑐) = (𝑏 ∪ 𝑐))
18	17	oveq2d 7428	. . . . . . . . . . 11 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐)) = (𝑎(+g‘𝑀)(𝑏 ∪ 𝑐)))
19		simpll 779	. . . . . . . . . . . . 13 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → 𝑎 ∈ 𝒫 𝐴)
20		pwuncl 7773	. . . . . . . . . . . . . 14 ⊢ ((𝑏 ∈ 𝒫 𝐴 ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑏 ∪ 𝑐) ∈ 𝒫 𝐴)
21	20	adantll 727	. . . . . . . . . . . . 13 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑏 ∪ 𝑐) ∈ 𝒫 𝐴)
22	19, 21	jca 521	. . . . . . . . . . . 12 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑎 ∈ 𝒫 𝐴 ∧ (𝑏 ∪ 𝑐) ∈ 𝒫 𝐴))
23	1, 5	pwmndgplus 19121	. . . . . . . . . . . 12 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ (𝑏 ∪ 𝑐) ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)(𝑏 ∪ 𝑐)) = (𝑎 ∪ (𝑏 ∪ 𝑐)))
24	22, 23	syl 18	. . . . . . . . . . 11 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)(𝑏 ∪ 𝑐)) = (𝑎 ∪ (𝑏 ∪ 𝑐)))
25	18, 24	eqtrd 2796	. . . . . . . . . 10 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐)) = (𝑎 ∪ (𝑏 ∪ 𝑐)))
26	10, 15, 25	3eqtr4a 2822	. . . . . . . . 9 ⊢ (((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) ∧ 𝑐 ∈ 𝒫 𝐴) → ((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐)))
27	26	ex 418	. . . . . . . 8 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) → (𝑐 ∈ 𝒫 𝐴 → ((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐))))
28	9, 27	biimtrid 245	. . . . . . 7 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) → (𝑐 ∈ (Base‘𝑀) → ((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐))))
29	28	ralrimiv 3154	. . . . . 6 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) → ∀𝑐 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐)))
30	8, 29	jca 521	. . . . 5 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ 𝑏 ∈ 𝒫 𝐴) → ((𝑎(+g‘𝑀)𝑏) ∈ (Base‘𝑀) ∧ ∀𝑐 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐))))
31	2, 3, 30	syl2anb 610	. . . 4 ⊢ ((𝑎 ∈ (Base‘𝑀) ∧ 𝑏 ∈ (Base‘𝑀)) → ((𝑎(+g‘𝑀)𝑏) ∈ (Base‘𝑀) ∧ ∀𝑐 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐))))
32	31	rgen2 3203	. . 3 ⊢ ∀𝑎 ∈ (Base‘𝑀)∀𝑏 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏) ∈ (Base‘𝑀) ∧ ∀𝑐 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐)))
33		0ex 5261	. . . . 5 ⊢ ∅ ∈ V
34		eleq1 2849	. . . . . 6 ⊢ (𝑒 = ∅ → (𝑒 ∈ (Base‘𝑀) ↔ ∅ ∈ (Base‘𝑀)))
35		oveq1 7419	. . . . . . . . 9 ⊢ (𝑒 = ∅ → (𝑒(+g‘𝑀)𝑎) = (∅(+g‘𝑀)𝑎))
36	35	eqeq1d 2763	. . . . . . . 8 ⊢ (𝑒 = ∅ → ((𝑒(+g‘𝑀)𝑎) = 𝑎 ↔ (∅(+g‘𝑀)𝑎) = 𝑎))
37		oveq2 7420	. . . . . . . . 9 ⊢ (𝑒 = ∅ → (𝑎(+g‘𝑀)𝑒) = (𝑎(+g‘𝑀)∅))
38	37	eqeq1d 2763	. . . . . . . 8 ⊢ (𝑒 = ∅ → ((𝑎(+g‘𝑀)𝑒) = 𝑎 ↔ (𝑎(+g‘𝑀)∅) = 𝑎))
39	36, 38	anbi12d 644	. . . . . . 7 ⊢ (𝑒 = ∅ → (((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎) ↔ ((∅(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)∅) = 𝑎)))
40	39	ralbidv 3186	. . . . . 6 ⊢ (𝑒 = ∅ → (∀𝑎 ∈ (Base‘𝑀)((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎) ↔ ∀𝑎 ∈ (Base‘𝑀)((∅(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)∅) = 𝑎)))
41	34, 40	anbi12d 644	. . . . 5 ⊢ (𝑒 = ∅ → ((𝑒 ∈ (Base‘𝑀) ∧ ∀𝑎 ∈ (Base‘𝑀)((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎)) ↔ (∅ ∈ (Base‘𝑀) ∧ ∀𝑎 ∈ (Base‘𝑀)((∅(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)∅) = 𝑎))))
42		0elpw 5317	. . . . . . 7 ⊢ ∅ ∈ 𝒫 𝐴
43	42, 1	eleqtrri 2860	. . . . . 6 ⊢ ∅ ∈ (Base‘𝑀)
44	1, 5	pwmndgplus 19121	. . . . . . . . . . 11 ⊢ ((∅ ∈ 𝒫 𝐴 ∧ 𝑎 ∈ 𝒫 𝐴) → (∅(+g‘𝑀)𝑎) = (∅ ∪ 𝑎))
45		0un 4346	. . . . . . . . . . 11 ⊢ (∅ ∪ 𝑎) = 𝑎
46	44, 45	eqtrdi 2812	. . . . . . . . . 10 ⊢ ((∅ ∈ 𝒫 𝐴 ∧ 𝑎 ∈ 𝒫 𝐴) → (∅(+g‘𝑀)𝑎) = 𝑎)
47	1, 5	pwmndgplus 19121	. . . . . . . . . . . 12 ⊢ ((𝑎 ∈ 𝒫 𝐴 ∧ ∅ ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)∅) = (𝑎 ∪ ∅))
48	47	ancoms 464	. . . . . . . . . . 11 ⊢ ((∅ ∈ 𝒫 𝐴 ∧ 𝑎 ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)∅) = (𝑎 ∪ ∅))
49		un0 4344	. . . . . . . . . . 11 ⊢ (𝑎 ∪ ∅) = 𝑎
50	48, 49	eqtrdi 2812	. . . . . . . . . 10 ⊢ ((∅ ∈ 𝒫 𝐴 ∧ 𝑎 ∈ 𝒫 𝐴) → (𝑎(+g‘𝑀)∅) = 𝑎)
51	46, 50	jca 521	. . . . . . . . 9 ⊢ ((∅ ∈ 𝒫 𝐴 ∧ 𝑎 ∈ 𝒫 𝐴) → ((∅(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)∅) = 𝑎))
52	42, 51	mpan 703	. . . . . . . 8 ⊢ (𝑎 ∈ 𝒫 𝐴 → ((∅(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)∅) = 𝑎))
53	2, 52	sylbi 220	. . . . . . 7 ⊢ (𝑎 ∈ (Base‘𝑀) → ((∅(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)∅) = 𝑎))
54	53	rgen 3079	. . . . . 6 ⊢ ∀𝑎 ∈ (Base‘𝑀)((∅(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)∅) = 𝑎)
55	43, 54	pm3.2i 476	. . . . 5 ⊢ (∅ ∈ (Base‘𝑀) ∧ ∀𝑎 ∈ (Base‘𝑀)((∅(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)∅) = 𝑎))
56	33, 41, 55	ceqsexv2d 3500	. . . 4 ⊢ ∃𝑒(𝑒 ∈ (Base‘𝑀) ∧ ∀𝑎 ∈ (Base‘𝑀)((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎))
57		df-rex 3088	. . . 4 ⊢ (∃𝑒 ∈ (Base‘𝑀)∀𝑎 ∈ (Base‘𝑀)((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎) ↔ ∃𝑒(𝑒 ∈ (Base‘𝑀) ∧ ∀𝑎 ∈ (Base‘𝑀)((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎)))
58	56, 57	mpbir 234	. . 3 ⊢ ∃𝑒 ∈ (Base‘𝑀)∀𝑎 ∈ (Base‘𝑀)((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎)
59	32, 58	pm3.2i 476	. 2 ⊢ (∀𝑎 ∈ (Base‘𝑀)∀𝑏 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏) ∈ (Base‘𝑀) ∧ ∀𝑐 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐))) ∧ ∃𝑒 ∈ (Base‘𝑀)∀𝑎 ∈ (Base‘𝑀)((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎))
60		eqid 2761	. . 3 ⊢ (Base‘𝑀) = (Base‘𝑀)
61		eqid 2761	. . 3 ⊢ (+g‘𝑀) = (+g‘𝑀)
62	60, 61	ismnd 18906	. 2 ⊢ (𝑀 ∈ Mnd ↔ (∀𝑎 ∈ (Base‘𝑀)∀𝑏 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏) ∈ (Base‘𝑀) ∧ ∀𝑐 ∈ (Base‘𝑀)((𝑎(+g‘𝑀)𝑏)(+g‘𝑀)𝑐) = (𝑎(+g‘𝑀)(𝑏(+g‘𝑀)𝑐))) ∧ ∃𝑒 ∈ (Base‘𝑀)∀𝑎 ∈ (Base‘𝑀)((𝑒(+g‘𝑀)𝑎) = 𝑎 ∧ (𝑎(+g‘𝑀)𝑒) = 𝑎)))
63	59, 62	mpbir 234	1 ⊢ 𝑀 ∈ Mnd

This proof depends on syntax axioms:   ∧ wa 401   = wceq 1570  ∃wex 1812   ∈ wcel 2145  ∀wral 3077  ∃wrex 3087   ∪ cun 3897  ∅c0 4279  𝒫 cpw 4557  ‘cfv 6531  (class class class)co 7412   ∈ cmpo 7414  Basecbs 17367  +_gcplusg 17408  Mndcmnd 18903

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 2213  ax-ext 2733  ax-sep 5249  ax-nul 5260  ax-pr 5391  ax-un 7740

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 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-ral 3078  df-rex 3088  df-rab 3414  df-v 3453  df-sbc 3740  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4280  df-if 4483  df-pw 4559  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5104  df-opab 5168  df-id 5546  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-iota 6487  df-fun 6533  df-fv 6539  df-ov 7415  df-oprab 7416  df-mpo 7417  df-mgm 18796  df-sgrp 18888  df-mnd 18904

This theorem is used by: (None)