Metamath Proof Explorer

Theorem latnlej2

Description: An idiom to express that a lattice element differs from two others. (Contributed by NM, 10-Jul-2012)

Ref Expression
Hypotheses latlej.b ⊢ 𝐵 = ( Base ‘ 𝐾 )
latlej.l ⊢ ≤ = ( le ‘ 𝐾 )
latlej.j ⊢ ∨ = ( join ‘ 𝐾 )
Assertion latnlej2 ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ∧ ¬ 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) ) → ( ¬ 𝑋 ≤ 𝑌 ∧ ¬ 𝑋 ≤ 𝑍 ) )

Proof

Step Hyp Ref Expression
1 latlej.b ⊢ 𝐵 = ( Base ‘ 𝐾 )
2 latlej.l ⊢ ≤ = ( le ‘ 𝐾 )
3 latlej.j ⊢ ∨ = ( join ‘ 𝐾 )
4 1 2 3 latlej1 ⊢ ( ( 𝐾 ∈ Lat ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) → 𝑌 ≤ ( 𝑌 ∨ 𝑍 ) )
5 4 3adant3r1 ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → 𝑌 ≤ ( 𝑌 ∨ 𝑍 ) )
6 simpl ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → 𝐾 ∈ Lat )
7 simpr1 ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → 𝑋 ∈ 𝐵 )
8 simpr2 ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → 𝑌 ∈ 𝐵 )
9 1 3 latjcl ⊢ ( ( 𝐾 ∈ Lat ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) → ( 𝑌 ∨ 𝑍 ) ∈ 𝐵 )
10 9 3adant3r1 ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → ( 𝑌 ∨ 𝑍 ) ∈ 𝐵 )
11 1 2 lattr ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ ( 𝑌 ∨ 𝑍 ) ∈ 𝐵 ) ) → ( ( 𝑋 ≤ 𝑌 ∧ 𝑌 ≤ ( 𝑌 ∨ 𝑍 ) ) → 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) ) )
12 6 7 8 10 11 syl13anc ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → ( ( 𝑋 ≤ 𝑌 ∧ 𝑌 ≤ ( 𝑌 ∨ 𝑍 ) ) → 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) ) )
13 5 12 mpan2d ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → ( 𝑋 ≤ 𝑌 → 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) ) )
14 13 con3d ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → ( ¬ 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) → ¬ 𝑋 ≤ 𝑌 ) )
15 1 2 3 latlej2 ⊢ ( ( 𝐾 ∈ Lat ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) → 𝑍 ≤ ( 𝑌 ∨ 𝑍 ) )
16 15 3adant3r1 ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → 𝑍 ≤ ( 𝑌 ∨ 𝑍 ) )
17 simpr3 ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → 𝑍 ∈ 𝐵 )
18 1 2 lattr ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ∧ ( 𝑌 ∨ 𝑍 ) ∈ 𝐵 ) ) → ( ( 𝑋 ≤ 𝑍 ∧ 𝑍 ≤ ( 𝑌 ∨ 𝑍 ) ) → 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) ) )
19 6 7 17 10 18 syl13anc ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → ( ( 𝑋 ≤ 𝑍 ∧ 𝑍 ≤ ( 𝑌 ∨ 𝑍 ) ) → 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) ) )
20 16 19 mpan2d ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → ( 𝑋 ≤ 𝑍 → 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) ) )
21 20 con3d ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → ( ¬ 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) → ¬ 𝑋 ≤ 𝑍 ) )
22 14 21 jcad ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ) → ( ¬ 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) → ( ¬ 𝑋 ≤ 𝑌 ∧ ¬ 𝑋 ≤ 𝑍 ) ) )
23 22 3impia ⊢ ( ( 𝐾 ∈ Lat ∧ ( 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵 ) ∧ ¬ 𝑋 ≤ ( 𝑌 ∨ 𝑍 ) ) → ( ¬ 𝑋 ≤ 𝑌 ∧ ¬ 𝑋 ≤ 𝑍 ) )