Metamath Proof Explorer


Theorem cmj1i

Description: A Hilbert lattice element commutes with its join. (Contributed by NM, 7-Aug-2004) (New usage is discouraged.)

Ref Expression
Hypotheses pjoml2.1 ⊢ A ∈ C ℋ
pjoml2.2 ⊢ B ∈ C ℋ
Assertion cmj1i ⊢ A 𝐶 ℋ A ∨ ℋ B

Proof

Step Hyp Ref Expression
1 pjoml2.1 ⊢ A ∈ C ℋ
2 pjoml2.2 ⊢ B ∈ C ℋ
3 1 2 chjcli ⊢ A ∨ ℋ B ∈ C ℋ
4 1 2 chub1i ⊢ A ⊆ A ∨ ℋ B
5 1 3 4 lecmii ⊢ A 𝐶 ℋ A ∨ ℋ B