Metamath Proof Explorer


Theorem chj1i

Description: Join with Hilbert lattice one. (Contributed by NM, 6-Aug-2004) (New usage is discouraged.)

Ref Expression
Hypothesis ch0le.1 ⊢ A ∈ C ℋ
Assertion chj1i ⊢ A ∨ ℋ ℋ = ℋ

Proof

Step Hyp Ref Expression
1 ch0le.1 ⊢ A ∈ C ℋ
2 helch ⊢ ℋ ∈ C ℋ
3 1 2 chjcli ⊢ A ∨ ℋ ℋ ∈ C ℋ
4 3 chssii ⊢ A ∨ ℋ ℋ ⊆ ℋ
5 2 1 chub2i ⊢ ℋ ⊆ A ∨ ℋ ℋ
6 4 5 eqssi ⊢ A ∨ ℋ ℋ = ℋ