Metamath Proof Explorer


Theorem lplnriaN

Description: Property of a lattice plane expressed as the join of 3 atoms. (Contributed by NM, 30-Jul-2012) (New usage is discouraged.)

Ref Expression
Hypotheses islpln2a.l
|- .<_ = ( le ` K )
islpln2a.j
|- .\/ = ( join ` K )
islpln2a.a
|- A = ( Atoms ` K )
islpln2a.p
|- P = ( LPlanes ` K )
islpln2a.y
|- Y = ( ( Q .\/ R ) .\/ S )
Assertion lplnriaN
|- ( ( K e. HL /\ ( Q e. A /\ R e. A /\ S e. A ) /\ Y e. P ) -> -. Q .<_ ( R .\/ S ) )

Proof

Step Hyp Ref Expression
1 islpln2a.l
 |-  .<_ = ( le ` K )
2 islpln2a.j
 |-  .\/ = ( join ` K )
3 islpln2a.a
 |-  A = ( Atoms ` K )
4 islpln2a.p
 |-  P = ( LPlanes ` K )
5 islpln2a.y
 |-  Y = ( ( Q .\/ R ) .\/ S )
6 1 2 3 4 5 islpln2ah
 |-  ( ( K e. HL /\ ( Q e. A /\ R e. A /\ S e. A ) ) -> ( Y e. P <-> ( Q =/= R /\ -. S .<_ ( Q .\/ R ) ) ) )
7 1 2 3 hlatcon3
 |-  ( ( K e. HL /\ ( Q e. A /\ R e. A /\ S e. A ) /\ ( Q =/= R /\ -. S .<_ ( Q .\/ R ) ) ) -> -. Q .<_ ( R .\/ S ) )
8 7 3expia
 |-  ( ( K e. HL /\ ( Q e. A /\ R e. A /\ S e. A ) ) -> ( ( Q =/= R /\ -. S .<_ ( Q .\/ R ) ) -> -. Q .<_ ( R .\/ S ) ) )
9 6 8 sylbid
 |-  ( ( K e. HL /\ ( Q e. A /\ R e. A /\ S e. A ) ) -> ( Y e. P -> -. Q .<_ ( R .\/ S ) ) )
10 9 3impia
 |-  ( ( K e. HL /\ ( Q e. A /\ R e. A /\ S e. A ) /\ Y e. P ) -> -. Q .<_ ( R .\/ S ) )