Theorem insubm 18877

Description: The intersection of two submonoids is a submonoid. (Contributed by AV, 25-Feb-2024.)

Assertion

Ref	Expression
insubm	⊢ ((𝐴 ∈ (SubMnd‘𝑀) ∧ 𝐵 ∈ (SubMnd‘𝑀)) → (𝐴 ∩ 𝐵) ∈ (SubMnd‘𝑀))

Proof of Theorem insubm

Dummy variables 𝑎 𝑏 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		submrcl 18860	. . 3 ⊢ (𝐴 ∈ (SubMnd‘𝑀) → 𝑀 ∈ Mnd)
2		ssinss1 4206	. . . . . . . . 9 ⊢ (𝐴 ⊆ (Base‘𝑀) → (𝐴 ∩ 𝐵) ⊆ (Base‘𝑀))
3	2	3ad2ant1 1149	. . . . . . . 8 ⊢ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) → (𝐴 ∩ 𝐵) ⊆ (Base‘𝑀))
4	3	ad2antrl 740	. . . . . . 7 ⊢ ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) → (𝐴 ∩ 𝐵) ⊆ (Base‘𝑀))
5		elin 3929	. . . . . . . . . . . . 13 ⊢ ((0g‘𝑀) ∈ (𝐴 ∩ 𝐵) ↔ ((0g‘𝑀) ∈ 𝐴 ∧ (0g‘𝑀) ∈ 𝐵))
6	5	simplbi2com 507	. . . . . . . . . . . 12 ⊢ ((0g‘𝑀) ∈ 𝐵 → ((0g‘𝑀) ∈ 𝐴 → (0g‘𝑀) ∈ (𝐴 ∩ 𝐵)))
7	6	3ad2ant2 1150	. . . . . . . . . . 11 ⊢ ((𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵) → ((0g‘𝑀) ∈ 𝐴 → (0g‘𝑀) ∈ (𝐴 ∩ 𝐵)))
8	7	com12 33	. . . . . . . . . 10 ⊢ ((0g‘𝑀) ∈ 𝐴 → ((𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵) → (0g‘𝑀) ∈ (𝐴 ∩ 𝐵)))
9	8	3ad2ant2 1150	. . . . . . . . 9 ⊢ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) → ((𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵) → (0g‘𝑀) ∈ (𝐴 ∩ 𝐵)))
10	9	imp 411	. . . . . . . 8 ⊢ (((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵)) → (0g‘𝑀) ∈ (𝐴 ∩ 𝐵))
11	10	adantl 486	. . . . . . 7 ⊢ ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) → (0g‘𝑀) ∈ (𝐴 ∩ 𝐵))
12		elin 3929	. . . . . . . . . 10 ⊢ (𝑥 ∈ (𝐴 ∩ 𝐵) ↔ (𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵))
13		elin 3929	. . . . . . . . . 10 ⊢ (𝑦 ∈ (𝐴 ∩ 𝐵) ↔ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵))
14	12, 13	anbi12i 639	. . . . . . . . 9 ⊢ ((𝑥 ∈ (𝐴 ∩ 𝐵) ∧ 𝑦 ∈ (𝐴 ∩ 𝐵)) ↔ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)))
15		oveq1 7418	. . . . . . . . . . . . . . . . 17 ⊢ (𝑎 = 𝑥 → (𝑎(+g‘𝑀)𝑏) = (𝑥(+g‘𝑀)𝑏))
16	15	eleq1d 2854	. . . . . . . . . . . . . . . 16 ⊢ (𝑎 = 𝑥 → ((𝑎(+g‘𝑀)𝑏) ∈ 𝐴 ↔ (𝑥(+g‘𝑀)𝑏) ∈ 𝐴))
17		oveq2 7419	. . . . . . . . . . . . . . . . 17 ⊢ (𝑏 = 𝑦 → (𝑥(+g‘𝑀)𝑏) = (𝑥(+g‘𝑀)𝑦))
18	17	eleq1d 2854	. . . . . . . . . . . . . . . 16 ⊢ (𝑏 = 𝑦 → ((𝑥(+g‘𝑀)𝑏) ∈ 𝐴 ↔ (𝑥(+g‘𝑀)𝑦) ∈ 𝐴))
19		simpl 487	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) → 𝑥 ∈ 𝐴)
20	19	adantr 485	. . . . . . . . . . . . . . . 16 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → 𝑥 ∈ 𝐴)
21		eqidd 2770	. . . . . . . . . . . . . . . 16 ⊢ ((((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) ∧ 𝑎 = 𝑥) → 𝐴 = 𝐴)
22		simpl 487	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝑦 ∈ 𝐴)
23	22	adantl 486	. . . . . . . . . . . . . . . 16 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → 𝑦 ∈ 𝐴)
24	16, 18, 20, 21, 23	rspc2vd 3909	. . . . . . . . . . . . . . 15 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴 → (𝑥(+g‘𝑀)𝑦) ∈ 𝐴))
25	24	com12 33	. . . . . . . . . . . . . 14 ⊢ (∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴 → (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐴))
26	25	3ad2ant3 1151	. . . . . . . . . . . . 13 ⊢ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) → (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐴))
27	26	ad2antrl 740	. . . . . . . . . . . 12 ⊢ ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) → (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐴))
28	27	imp 411	. . . . . . . . . . 11 ⊢ (((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) ∧ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵))) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐴)
29	15	eleq1d 2854	. . . . . . . . . . . . . . . . 17 ⊢ (𝑎 = 𝑥 → ((𝑎(+g‘𝑀)𝑏) ∈ 𝐵 ↔ (𝑥(+g‘𝑀)𝑏) ∈ 𝐵))
30	17	eleq1d 2854	. . . . . . . . . . . . . . . . 17 ⊢ (𝑏 = 𝑦 → ((𝑥(+g‘𝑀)𝑏) ∈ 𝐵 ↔ (𝑥(+g‘𝑀)𝑦) ∈ 𝐵))
31		simpr 489	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) → 𝑥 ∈ 𝐵)
32	31	adantr 485	. . . . . . . . . . . . . . . . 17 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → 𝑥 ∈ 𝐵)
33		eqidd 2770	. . . . . . . . . . . . . . . . 17 ⊢ ((((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) ∧ 𝑎 = 𝑥) → 𝐵 = 𝐵)
34		simpr 489	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝑦 ∈ 𝐵)
35	34	adantl 486	. . . . . . . . . . . . . . . . 17 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → 𝑦 ∈ 𝐵)
36	29, 30, 32, 33, 35	rspc2vd 3909	. . . . . . . . . . . . . . . 16 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵 → (𝑥(+g‘𝑀)𝑦) ∈ 𝐵))
37	36	com12 33	. . . . . . . . . . . . . . 15 ⊢ (∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵 → (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐵))
38	37	3ad2ant3 1151	. . . . . . . . . . . . . 14 ⊢ ((𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵) → (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐵))
39	38	adantl 486	. . . . . . . . . . . . 13 ⊢ (((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵)) → (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐵))
40	39	adantl 486	. . . . . . . . . . . 12 ⊢ ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) → (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐵))
41	40	imp 411	. . . . . . . . . . 11 ⊢ (((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) ∧ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵))) → (𝑥(+g‘𝑀)𝑦) ∈ 𝐵)
42	28, 41	elind 4161	. . . . . . . . . 10 ⊢ (((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) ∧ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵))) → (𝑥(+g‘𝑀)𝑦) ∈ (𝐴 ∩ 𝐵))
43	42	ex 417	. . . . . . . . 9 ⊢ ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) → (((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ (𝐴 ∩ 𝐵)))
44	14, 43	biimtrid 245	. . . . . . . 8 ⊢ ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) → ((𝑥 ∈ (𝐴 ∩ 𝐵) ∧ 𝑦 ∈ (𝐴 ∩ 𝐵)) → (𝑥(+g‘𝑀)𝑦) ∈ (𝐴 ∩ 𝐵)))
45	44	ralrimivv 3212	. . . . . . 7 ⊢ ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) → ∀𝑥 ∈ (𝐴 ∩ 𝐵)∀𝑦 ∈ (𝐴 ∩ 𝐵)(𝑥(+g‘𝑀)𝑦) ∈ (𝐴 ∩ 𝐵))
46	4, 11, 45	3jca 1144	. . . . . 6 ⊢ ((𝑀 ∈ Mnd ∧ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))) → ((𝐴 ∩ 𝐵) ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ (𝐴 ∩ 𝐵) ∧ ∀𝑥 ∈ (𝐴 ∩ 𝐵)∀𝑦 ∈ (𝐴 ∩ 𝐵)(𝑥(+g‘𝑀)𝑦) ∈ (𝐴 ∩ 𝐵)))
47	46	ex 417	. . . . 5 ⊢ (𝑀 ∈ Mnd → (((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵)) → ((𝐴 ∩ 𝐵) ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ (𝐴 ∩ 𝐵) ∧ ∀𝑥 ∈ (𝐴 ∩ 𝐵)∀𝑦 ∈ (𝐴 ∩ 𝐵)(𝑥(+g‘𝑀)𝑦) ∈ (𝐴 ∩ 𝐵))))
48		eqid 2769	. . . . . . 7 ⊢ (Base‘𝑀) = (Base‘𝑀)
49		eqid 2769	. . . . . . 7 ⊢ (0g‘𝑀) = (0g‘𝑀)
50		eqid 2769	. . . . . . 7 ⊢ (+g‘𝑀) = (+g‘𝑀)
51	48, 49, 50	issubm 18861	. . . . . 6 ⊢ (𝑀 ∈ Mnd → (𝐴 ∈ (SubMnd‘𝑀) ↔ (𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴)))
52	48, 49, 50	issubm 18861	. . . . . 6 ⊢ (𝑀 ∈ Mnd → (𝐵 ∈ (SubMnd‘𝑀) ↔ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵)))
53	51, 52	anbi12d 643	. . . . 5 ⊢ (𝑀 ∈ Mnd → ((𝐴 ∈ (SubMnd‘𝑀) ∧ 𝐵 ∈ (SubMnd‘𝑀)) ↔ ((𝐴 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐴 ∧ ∀𝑎 ∈ 𝐴 ∀𝑏 ∈ 𝐴 (𝑎(+g‘𝑀)𝑏) ∈ 𝐴) ∧ (𝐵 ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ 𝐵 ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 (𝑎(+g‘𝑀)𝑏) ∈ 𝐵))))
54	48, 49, 50	issubm 18861	. . . . 5 ⊢ (𝑀 ∈ Mnd → ((𝐴 ∩ 𝐵) ∈ (SubMnd‘𝑀) ↔ ((𝐴 ∩ 𝐵) ⊆ (Base‘𝑀) ∧ (0g‘𝑀) ∈ (𝐴 ∩ 𝐵) ∧ ∀𝑥 ∈ (𝐴 ∩ 𝐵)∀𝑦 ∈ (𝐴 ∩ 𝐵)(𝑥(+g‘𝑀)𝑦) ∈ (𝐴 ∩ 𝐵))))
55	47, 53, 54	3imtr4d 297	. . . 4 ⊢ (𝑀 ∈ Mnd → ((𝐴 ∈ (SubMnd‘𝑀) ∧ 𝐵 ∈ (SubMnd‘𝑀)) → (𝐴 ∩ 𝐵) ∈ (SubMnd‘𝑀)))
56	55	expd 420	. . 3 ⊢ (𝑀 ∈ Mnd → (𝐴 ∈ (SubMnd‘𝑀) → (𝐵 ∈ (SubMnd‘𝑀) → (𝐴 ∩ 𝐵) ∈ (SubMnd‘𝑀))))
57	1, 56	mpcom 39	. 2 ⊢ (𝐴 ∈ (SubMnd‘𝑀) → (𝐵 ∈ (SubMnd‘𝑀) → (𝐴 ∩ 𝐵) ∈ (SubMnd‘𝑀)))
58	57	imp 411	1 ⊢ ((𝐴 ∈ (SubMnd‘𝑀) ∧ 𝐵 ∈ (SubMnd‘𝑀)) → (𝐴 ∩ 𝐵) ∈ (SubMnd‘𝑀))

Syntax hints:   → wi 4   ∧ wa 400   ∧ w3a 1101   ∈ wcel 2149  ∀wral 3085   ∩ cin 3912   ⊆ wss 3913  ‘cfv 6537  (class class class)co 7411  Basecbs 17269  +_gcplusg 17310  0_gc0g 17492  Mndcmnd 18792  SubMndcsubmnd 18840

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1822  ax-4 1836  ax-5 1937  ax-6 1994  ax-7 2035  ax-8 2151  ax-9 2159  ax-10 2182  ax-11 2198  ax-12 2219  ax-ext 2741  ax-sep 5261  ax-nul 5271  ax-pow 5337  ax-pr 5405

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1103  df-tru 1570  df-fal 1580  df-ex 1807  df-nf 1811  df-sb 2098  df-mo 2573  df-eu 2603  df-clab 2748  df-cleq 2761  df-clel 2844  df-nfc 2918  df-ne 2965  df-ral 3086  df-rex 3096  df-rab 3424  df-v 3465  df-sbc 3754  df-csb 3862  df-dif 3916  df-un 3918  df-in 3920  df-ss 3930  df-nul 4295  df-if 4493  df-pw 4569  df-sn 4595  df-pr 4597  df-op 4601  df-uni 4877  df-br 5114  df-opab 5178  df-mpt 5197  df-id 5557  df-xp 5668  df-rel 5669  df-cnv 5670  df-co 5671  df-dm 5672  df-rn 5673  df-res 5674  df-ima 5675  df-iota 6493  df-fun 6539  df-fv 6545  df-ov 7414  df-submnd 18842

This theorem is referenced by:  symgsubmefmnd  19468