Metamath Proof Explorer


Theorem chub2

Description: Hilbert lattice join is greater than or equal to its second argument. (Contributed by NM, 12-Jun-2004) (New usage is discouraged.)

Ref Expression
Assertion chub2 ( ( 𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) → 𝐴 ⊆ ( 𝐵 ∨ℋ 𝐴 ) )

Proof

Step Hyp Ref Expression
1 chub1 ⊢ ( ( 𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) → 𝐴 ⊆ ( 𝐴 ∨ℋ 𝐵 ) )
2 chjcom ⊢ ( ( 𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) → ( 𝐴 ∨ℋ 𝐵 ) = ( 𝐵 ∨ℋ 𝐴 ) )
3 1 2 sseqtrd ⊢ ( ( 𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) → 𝐴 ⊆ ( 𝐵 ∨ℋ 𝐴 ) )