| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dicvscacl.l |  |-  .<_ = ( le ` K ) | 
						
							| 2 |  | dicvscacl.a |  |-  A = ( Atoms ` K ) | 
						
							| 3 |  | dicvscacl.h |  |-  H = ( LHyp ` K ) | 
						
							| 4 |  | dicvscacl.e |  |-  E = ( ( TEndo ` K ) ` W ) | 
						
							| 5 |  | dicvscacl.u |  |-  U = ( ( DVecH ` K ) ` W ) | 
						
							| 6 |  | dicvscacl.i |  |-  I = ( ( DIsoC ` K ) ` W ) | 
						
							| 7 |  | dicvscacl.s |  |-  .x. = ( .s ` U ) | 
						
							| 8 |  | simp1 |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( K e. HL /\ W e. H ) ) | 
						
							| 9 |  | simp3l |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> X e. E ) | 
						
							| 10 |  | eqid |  |-  ( Base ` U ) = ( Base ` U ) | 
						
							| 11 | 1 2 3 6 5 10 | dicssdvh |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) ) -> ( I ` Q ) C_ ( Base ` U ) ) | 
						
							| 12 |  | eqid |  |-  ( ( LTrn ` K ) ` W ) = ( ( LTrn ` K ) ` W ) | 
						
							| 13 | 3 12 4 5 10 | dvhvbase |  |-  ( ( K e. HL /\ W e. H ) -> ( Base ` U ) = ( ( ( LTrn ` K ) ` W ) X. E ) ) | 
						
							| 14 | 13 | eqcomd |  |-  ( ( K e. HL /\ W e. H ) -> ( ( ( LTrn ` K ) ` W ) X. E ) = ( Base ` U ) ) | 
						
							| 15 | 14 | adantr |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) ) -> ( ( ( LTrn ` K ) ` W ) X. E ) = ( Base ` U ) ) | 
						
							| 16 | 11 15 | sseqtrrd |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) ) -> ( I ` Q ) C_ ( ( ( LTrn ` K ) ` W ) X. E ) ) | 
						
							| 17 | 16 | 3adant3 |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( I ` Q ) C_ ( ( ( LTrn ` K ) ` W ) X. E ) ) | 
						
							| 18 |  | simp3r |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> Y e. ( I ` Q ) ) | 
						
							| 19 | 17 18 | sseldd |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> Y e. ( ( ( LTrn ` K ) ` W ) X. E ) ) | 
						
							| 20 | 3 12 4 5 7 | dvhvsca |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( X e. E /\ Y e. ( ( ( LTrn ` K ) ` W ) X. E ) ) ) -> ( X .x. Y ) = <. ( X ` ( 1st ` Y ) ) , ( X o. ( 2nd ` Y ) ) >. ) | 
						
							| 21 | 8 9 19 20 | syl12anc |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( X .x. Y ) = <. ( X ` ( 1st ` Y ) ) , ( X o. ( 2nd ` Y ) ) >. ) | 
						
							| 22 |  | fvi |  |-  ( X e. E -> ( _I ` X ) = X ) | 
						
							| 23 | 9 22 | syl |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( _I ` X ) = X ) | 
						
							| 24 | 23 | coeq1d |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( ( _I ` X ) o. ( 2nd ` Y ) ) = ( X o. ( 2nd ` Y ) ) ) | 
						
							| 25 | 24 | opeq2d |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> <. ( X ` ( 1st ` Y ) ) , ( ( _I ` X ) o. ( 2nd ` Y ) ) >. = <. ( X ` ( 1st ` Y ) ) , ( X o. ( 2nd ` Y ) ) >. ) | 
						
							| 26 | 21 25 | eqtr4d |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( X .x. Y ) = <. ( X ` ( 1st ` Y ) ) , ( ( _I ` X ) o. ( 2nd ` Y ) ) >. ) | 
						
							| 27 |  | eqid |  |-  ( ( oc ` K ) ` W ) = ( ( oc ` K ) ` W ) | 
						
							| 28 | 1 2 3 27 12 6 | dicelval1sta |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ Y e. ( I ` Q ) ) -> ( 1st ` Y ) = ( ( 2nd ` Y ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) ) | 
						
							| 29 | 28 | 3adant3l |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( 1st ` Y ) = ( ( 2nd ` Y ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) ) | 
						
							| 30 | 29 | fveq2d |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( X ` ( 1st ` Y ) ) = ( X ` ( ( 2nd ` Y ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) ) ) | 
						
							| 31 | 1 2 3 4 6 | dicelval2nd |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ Y e. ( I ` Q ) ) -> ( 2nd ` Y ) e. E ) | 
						
							| 32 | 31 | 3adant3l |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( 2nd ` Y ) e. E ) | 
						
							| 33 | 3 12 4 | tendof |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( 2nd ` Y ) e. E ) -> ( 2nd ` Y ) : ( ( LTrn ` K ) ` W ) --> ( ( LTrn ` K ) ` W ) ) | 
						
							| 34 | 8 32 33 | syl2anc |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( 2nd ` Y ) : ( ( LTrn ` K ) ` W ) --> ( ( LTrn ` K ) ` W ) ) | 
						
							| 35 |  | eqid |  |-  ( oc ` K ) = ( oc ` K ) | 
						
							| 36 | 1 35 2 3 | lhpocnel |  |-  ( ( K e. HL /\ W e. H ) -> ( ( ( oc ` K ) ` W ) e. A /\ -. ( ( oc ` K ) ` W ) .<_ W ) ) | 
						
							| 37 | 36 | 3ad2ant1 |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( ( ( oc ` K ) ` W ) e. A /\ -. ( ( oc ` K ) ` W ) .<_ W ) ) | 
						
							| 38 |  | simp2 |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( Q e. A /\ -. Q .<_ W ) ) | 
						
							| 39 |  | eqid |  |-  ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) = ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) | 
						
							| 40 | 1 2 3 12 39 | ltrniotacl |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( ( ( oc ` K ) ` W ) e. A /\ -. ( ( oc ` K ) ` W ) .<_ W ) /\ ( Q e. A /\ -. Q .<_ W ) ) -> ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) e. ( ( LTrn ` K ) ` W ) ) | 
						
							| 41 | 8 37 38 40 | syl3anc |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) e. ( ( LTrn ` K ) ` W ) ) | 
						
							| 42 |  | fvco3 |  |-  ( ( ( 2nd ` Y ) : ( ( LTrn ` K ) ` W ) --> ( ( LTrn ` K ) ` W ) /\ ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) e. ( ( LTrn ` K ) ` W ) ) -> ( ( X o. ( 2nd ` Y ) ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) = ( X ` ( ( 2nd ` Y ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) ) ) | 
						
							| 43 | 34 41 42 | syl2anc |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( ( X o. ( 2nd ` Y ) ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) = ( X ` ( ( 2nd ` Y ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) ) ) | 
						
							| 44 | 30 43 | eqtr4d |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( X ` ( 1st ` Y ) ) = ( ( X o. ( 2nd ` Y ) ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) ) | 
						
							| 45 | 24 | fveq1d |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( ( ( _I ` X ) o. ( 2nd ` Y ) ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) = ( ( X o. ( 2nd ` Y ) ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) ) | 
						
							| 46 | 44 45 | eqtr4d |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( X ` ( 1st ` Y ) ) = ( ( ( _I ` X ) o. ( 2nd ` Y ) ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) ) | 
						
							| 47 | 3 4 | tendococl |  |-  ( ( ( K e. HL /\ W e. H ) /\ X e. E /\ ( 2nd ` Y ) e. E ) -> ( X o. ( 2nd ` Y ) ) e. E ) | 
						
							| 48 | 8 9 32 47 | syl3anc |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( X o. ( 2nd ` Y ) ) e. E ) | 
						
							| 49 | 24 48 | eqeltrd |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( ( _I ` X ) o. ( 2nd ` Y ) ) e. E ) | 
						
							| 50 |  | fvex |  |-  ( X ` ( 1st ` Y ) ) e. _V | 
						
							| 51 |  | fvex |  |-  ( _I ` X ) e. _V | 
						
							| 52 |  | fvex |  |-  ( 2nd ` Y ) e. _V | 
						
							| 53 | 51 52 | coex |  |-  ( ( _I ` X ) o. ( 2nd ` Y ) ) e. _V | 
						
							| 54 | 1 2 3 27 12 4 6 50 53 | dicopelval |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) ) -> ( <. ( X ` ( 1st ` Y ) ) , ( ( _I ` X ) o. ( 2nd ` Y ) ) >. e. ( I ` Q ) <-> ( ( X ` ( 1st ` Y ) ) = ( ( ( _I ` X ) o. ( 2nd ` Y ) ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) /\ ( ( _I ` X ) o. ( 2nd ` Y ) ) e. E ) ) ) | 
						
							| 55 | 54 | 3adant3 |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( <. ( X ` ( 1st ` Y ) ) , ( ( _I ` X ) o. ( 2nd ` Y ) ) >. e. ( I ` Q ) <-> ( ( X ` ( 1st ` Y ) ) = ( ( ( _I ` X ) o. ( 2nd ` Y ) ) ` ( iota_ g e. ( ( LTrn ` K ) ` W ) ( g ` ( ( oc ` K ) ` W ) ) = Q ) ) /\ ( ( _I ` X ) o. ( 2nd ` Y ) ) e. E ) ) ) | 
						
							| 56 | 46 49 55 | mpbir2and |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> <. ( X ` ( 1st ` Y ) ) , ( ( _I ` X ) o. ( 2nd ` Y ) ) >. e. ( I ` Q ) ) | 
						
							| 57 | 26 56 | eqeltrd |  |-  ( ( ( K e. HL /\ W e. H ) /\ ( Q e. A /\ -. Q .<_ W ) /\ ( X e. E /\ Y e. ( I ` Q ) ) ) -> ( X .x. Y ) e. ( I ` Q ) ) |