Metamath Proof Explorer


Theorem atdmd2

Description: Two Hilbert lattice elements have the dual modular pair property if the second is an atom. (Contributed by NM, 6-Jul-2004) (New usage is discouraged.)

Ref Expression
Assertion atdmd2
|- ( ( A e. CH /\ B e. HAtoms ) -> A MH* B )

Proof

Step Hyp Ref Expression
1 atdmd
 |-  ( ( B e. HAtoms /\ A e. CH ) -> B MH* A )
2 1 ancoms
 |-  ( ( A e. CH /\ B e. HAtoms ) -> B MH* A )
3 atelch
 |-  ( B e. HAtoms -> B e. CH )
4 dmdsym
 |-  ( ( A e. CH /\ B e. CH ) -> ( A MH* B <-> B MH* A ) )
5 3 4 sylan2
 |-  ( ( A e. CH /\ B e. HAtoms ) -> ( A MH* B <-> B MH* A ) )
6 2 5 mpbird
 |-  ( ( A e. CH /\ B e. HAtoms ) -> A MH* B )