Theorem dlatmjdi 18712

Description: In a distributive lattice, meets distribute over joins. (Contributed by Stefan O'Rear, 30-Jan-2015.)

Hypotheses

Ref	Expression
isdlat.b	⊢ 𝐵 = (Base‘𝐾)
isdlat.j	⊢ ∨ = (join‘𝐾)
isdlat.m	⊢ ∧ = (meet‘𝐾)

Assertion

Ref	Expression
dlatmjdi	⊢ ((𝐾 ∈ DLat ∧ (𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵)) → (𝑋 ∧ (𝑌 ∨ 𝑍)) = ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑍)))

Proof of Theorem dlatmjdi

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

Step	Hyp	Ref	Expression
1		isdlat.b	. . . 4 ⊢ 𝐵 = (Base‘𝐾)
2		isdlat.j	. . . 4 ⊢ ∨ = (join‘𝐾)
3		isdlat.m	. . . 4 ⊢ ∧ = (meet‘𝐾)
4	1, 2, 3	isdlat 18711	. . 3 ⊢ (𝐾 ∈ DLat ↔ (𝐾 ∈ Lat ∧ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐵 (𝑥 ∧ (𝑦 ∨ 𝑧)) = ((𝑥 ∧ 𝑦) ∨ (𝑥 ∧ 𝑧))))
5	4	simprbi 503	. 2 ⊢ (𝐾 ∈ DLat → ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐵 (𝑥 ∧ (𝑦 ∨ 𝑧)) = ((𝑥 ∧ 𝑦) ∨ (𝑥 ∧ 𝑧)))
6		oveq1 7437	. . . 4 ⊢ (𝑥 = 𝑋 → (𝑥 ∧ (𝑦 ∨ 𝑧)) = (𝑋 ∧ (𝑦 ∨ 𝑧)))
7		oveq1 7437	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑥 ∧ 𝑦) = (𝑋 ∧ 𝑦))
8		oveq1 7437	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑥 ∧ 𝑧) = (𝑋 ∧ 𝑧))
9	7, 8	oveq12d 7448	. . . 4 ⊢ (𝑥 = 𝑋 → ((𝑥 ∧ 𝑦) ∨ (𝑥 ∧ 𝑧)) = ((𝑋 ∧ 𝑦) ∨ (𝑋 ∧ 𝑧)))
10	6, 9	eqeq12d 2779	. . 3 ⊢ (𝑥 = 𝑋 → ((𝑥 ∧ (𝑦 ∨ 𝑧)) = ((𝑥 ∧ 𝑦) ∨ (𝑥 ∧ 𝑧)) ↔ (𝑋 ∧ (𝑦 ∨ 𝑧)) = ((𝑋 ∧ 𝑦) ∨ (𝑋 ∧ 𝑧))))
11		oveq1 7437	. . . . 5 ⊢ (𝑦 = 𝑌 → (𝑦 ∨ 𝑧) = (𝑌 ∨ 𝑧))
12	11	oveq2d 7446	. . . 4 ⊢ (𝑦 = 𝑌 → (𝑋 ∧ (𝑦 ∨ 𝑧)) = (𝑋 ∧ (𝑌 ∨ 𝑧)))
13		oveq2 7438	. . . . 5 ⊢ (𝑦 = 𝑌 → (𝑋 ∧ 𝑦) = (𝑋 ∧ 𝑌))
14	13	oveq1d 7445	. . . 4 ⊢ (𝑦 = 𝑌 → ((𝑋 ∧ 𝑦) ∨ (𝑋 ∧ 𝑧)) = ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑧)))
15	12, 14	eqeq12d 2779	. . 3 ⊢ (𝑦 = 𝑌 → ((𝑋 ∧ (𝑦 ∨ 𝑧)) = ((𝑋 ∧ 𝑦) ∨ (𝑋 ∧ 𝑧)) ↔ (𝑋 ∧ (𝑌 ∨ 𝑧)) = ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑧))))
16		oveq2 7438	. . . . 5 ⊢ (𝑧 = 𝑍 → (𝑌 ∨ 𝑧) = (𝑌 ∨ 𝑍))
17	16	oveq2d 7446	. . . 4 ⊢ (𝑧 = 𝑍 → (𝑋 ∧ (𝑌 ∨ 𝑧)) = (𝑋 ∧ (𝑌 ∨ 𝑍)))
18		oveq2 7438	. . . . 5 ⊢ (𝑧 = 𝑍 → (𝑋 ∧ 𝑧) = (𝑋 ∧ 𝑍))
19	18	oveq2d 7446	. . . 4 ⊢ (𝑧 = 𝑍 → ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑧)) = ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑍)))
20	17, 19	eqeq12d 2779	. . 3 ⊢ (𝑧 = 𝑍 → ((𝑋 ∧ (𝑌 ∨ 𝑧)) = ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑧)) ↔ (𝑋 ∧ (𝑌 ∨ 𝑍)) = ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑍))))
21	10, 15, 20	rspc3v 3595	. 2 ⊢ ((𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵) → (∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐵 (𝑥 ∧ (𝑦 ∨ 𝑧)) = ((𝑥 ∧ 𝑦) ∨ (𝑥 ∧ 𝑧)) → (𝑋 ∧ (𝑌 ∨ 𝑍)) = ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑍))))
22	5, 21	mpan9 516	1 ⊢ ((𝐾 ∈ DLat ∧ (𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵)) → (𝑋 ∧ (𝑌 ∨ 𝑍)) = ((𝑋 ∧ 𝑌) ∨ (𝑋 ∧ 𝑍)))

This proof depends on syntax axioms:   → wi 4   ∧ wa 401   ∧ w3a 1103   = wceq 1569   ∈ wcel 2146  ∀wral 3080  ‘cfv 6547  (class class class)co 7430  Basecbs 17402  joincjn 18500  meetcmee 18501  Latclat 18620  DLatcdlat 18709

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 1944  ax-6 2001  ax-7 2042  ax-8 2148  ax-9 2156  ax-ext 2735  ax-nul 5263

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 2101  df-clab 2742  df-cleq 2755  df-clel 2839  df-ne 2960  df-ral 3081  df-rex 3091  df-rab 3417  df-v 3456  df-sbc 3743  df-ss 3901  df-dif 4050  df-un 4154  df-nul 4282  df-if 4486  df-sn 4589  df-pr 4591  df-op 4839  df-uni 4871  df-br 5107  df-iota 6501  df-fv 6555  df-ov 7433  df-dlat 18710

This theorem is used by:  dlatjmdi  18715