| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cdlemg4.l |  |-  .<_ = ( le ` K ) | 
						
							| 2 |  | cdlemg4.a |  |-  A = ( Atoms ` K ) | 
						
							| 3 |  | cdlemg4.h |  |-  H = ( LHyp ` K ) | 
						
							| 4 |  | cdlemg4.t |  |-  T = ( ( LTrn ` K ) ` W ) | 
						
							| 5 |  | cdlemg4.r |  |-  R = ( ( trL ` K ) ` W ) | 
						
							| 6 |  | cdlemg4.j |  |-  .\/ = ( join ` K ) | 
						
							| 7 |  | cdlemg4b.v |  |-  V = ( R ` G ) | 
						
							| 8 |  | eqid |  |-  ( meet ` K ) = ( meet ` K ) | 
						
							| 9 | 1 6 8 2 3 4 5 | trlval2 |  |-  ( ( ( K e. HL /\ W e. H ) /\ G e. T /\ ( P e. A /\ -. P .<_ W ) ) -> ( R ` G ) = ( ( P .\/ ( G ` P ) ) ( meet ` K ) W ) ) | 
						
							| 10 | 9 | 3com23 |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ -. P .<_ W ) /\ G e. T ) -> ( R ` G ) = ( ( P .\/ ( G ` P ) ) ( meet ` K ) W ) ) | 
						
							| 11 | 7 10 | eqtrid |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ -. P .<_ W ) /\ G e. T ) -> V = ( ( P .\/ ( G ` P ) ) ( meet ` K ) W ) ) | 
						
							| 12 | 11 | oveq2d |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ -. P .<_ W ) /\ G e. T ) -> ( ( G ` P ) .\/ V ) = ( ( G ` P ) .\/ ( ( P .\/ ( G ` P ) ) ( meet ` K ) W ) ) ) | 
						
							| 13 |  | simp1 |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ -. P .<_ W ) /\ G e. T ) -> ( K e. HL /\ W e. H ) ) | 
						
							| 14 |  | simp2l |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ -. P .<_ W ) /\ G e. T ) -> P e. A ) | 
						
							| 15 | 1 2 3 4 | ltrnel |  |-  ( ( ( K e. HL /\ W e. H ) /\ G e. T /\ ( P e. A /\ -. P .<_ W ) ) -> ( ( G ` P ) e. A /\ -. ( G ` P ) .<_ W ) ) | 
						
							| 16 | 15 | 3com23 |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ -. P .<_ W ) /\ G e. T ) -> ( ( G ` P ) e. A /\ -. ( G ` P ) .<_ W ) ) | 
						
							| 17 |  | eqid |  |-  ( ( P .\/ ( G ` P ) ) ( meet ` K ) W ) = ( ( P .\/ ( G ` P ) ) ( meet ` K ) W ) | 
						
							| 18 | 1 6 8 2 3 17 | cdleme0cq |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ ( ( G ` P ) e. A /\ -. ( G ` P ) .<_ W ) ) ) -> ( ( G ` P ) .\/ ( ( P .\/ ( G ` P ) ) ( meet ` K ) W ) ) = ( P .\/ ( G ` P ) ) ) | 
						
							| 19 | 13 14 16 18 | syl12anc |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ -. P .<_ W ) /\ G e. T ) -> ( ( G ` P ) .\/ ( ( P .\/ ( G ` P ) ) ( meet ` K ) W ) ) = ( P .\/ ( G ` P ) ) ) | 
						
							| 20 | 12 19 | eqtrd |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( P e. A /\ -. P .<_ W ) /\ G e. T ) -> ( ( G ` P ) .\/ V ) = ( P .\/ ( G ` P ) ) ) |