Metamath Proof Explorer


Theorem chincli

Description: Closure of Hilbert lattice intersection. (Contributed by NM, 15-Oct-1999) (New usage is discouraged.)

Ref Expression
Hypotheses ch0le.1
|- A e. CH
chjcl.2
|- B e. CH
Assertion chincli
|- ( A i^i B ) e. CH

Proof

Step Hyp Ref Expression
1 ch0le.1
 |-  A e. CH
2 chjcl.2
 |-  B e. CH
3 1 elexi
 |-  A e. _V
4 2 elexi
 |-  B e. _V
5 3 4 intpr
 |-  |^| { A , B } = ( A i^i B )
6 1 2 pm3.2i
 |-  ( A e. CH /\ B e. CH )
7 3 4 prss
 |-  ( ( A e. CH /\ B e. CH ) <-> { A , B } C_ CH )
8 6 7 mpbi
 |-  { A , B } C_ CH
9 3 prnz
 |-  { A , B } =/= (/)
10 8 9 pm3.2i
 |-  ( { A , B } C_ CH /\ { A , B } =/= (/) )
11 10 chintcli
 |-  |^| { A , B } e. CH
12 5 11 eqeltrri
 |-  ( A i^i B ) e. CH