| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mapdh8a.h |  |-  H = ( LHyp ` K ) | 
						
							| 2 |  | mapdh8a.u |  |-  U = ( ( DVecH ` K ) ` W ) | 
						
							| 3 |  | mapdh8a.v |  |-  V = ( Base ` U ) | 
						
							| 4 |  | mapdh8a.s |  |-  .- = ( -g ` U ) | 
						
							| 5 |  | mapdh8a.o |  |-  .0. = ( 0g ` U ) | 
						
							| 6 |  | mapdh8a.n |  |-  N = ( LSpan ` U ) | 
						
							| 7 |  | mapdh8a.c |  |-  C = ( ( LCDual ` K ) ` W ) | 
						
							| 8 |  | mapdh8a.d |  |-  D = ( Base ` C ) | 
						
							| 9 |  | mapdh8a.r |  |-  R = ( -g ` C ) | 
						
							| 10 |  | mapdh8a.q |  |-  Q = ( 0g ` C ) | 
						
							| 11 |  | mapdh8a.j |  |-  J = ( LSpan ` C ) | 
						
							| 12 |  | mapdh8a.m |  |-  M = ( ( mapd ` K ) ` W ) | 
						
							| 13 |  | mapdh8a.i |  |-  I = ( x e. _V |-> if ( ( 2nd ` x ) = .0. , Q , ( iota_ h e. D ( ( M ` ( N ` { ( 2nd ` x ) } ) ) = ( J ` { h } ) /\ ( M ` ( N ` { ( ( 1st ` ( 1st ` x ) ) .- ( 2nd ` x ) ) } ) ) = ( J ` { ( ( 2nd ` ( 1st ` x ) ) R h ) } ) ) ) ) ) | 
						
							| 14 |  | mapdh8a.k |  |-  ( ph -> ( K e. HL /\ W e. H ) ) | 
						
							| 15 |  | mapdh8e.f |  |-  ( ph -> F e. D ) | 
						
							| 16 |  | mapdh8e.mn |  |-  ( ph -> ( M ` ( N ` { X } ) ) = ( J ` { F } ) ) | 
						
							| 17 |  | mapdh8e.eg |  |-  ( ph -> ( I ` <. X , F , Y >. ) = G ) | 
						
							| 18 |  | mapdh8e.x |  |-  ( ph -> X e. ( V \ { .0. } ) ) | 
						
							| 19 |  | mapdh8e.y |  |-  ( ph -> Y e. ( V \ { .0. } ) ) | 
						
							| 20 |  | mapdh8e.t |  |-  ( ph -> T e. ( V \ { .0. } ) ) | 
						
							| 21 |  | mapdh8e.xy |  |-  ( ph -> ( N ` { X } ) =/= ( N ` { Y } ) ) | 
						
							| 22 |  | mapdh8e.xt |  |-  ( ph -> ( N ` { X } ) =/= ( N ` { T } ) ) | 
						
							| 23 |  | mapdh8e.yt |  |-  ( ph -> ( N ` { Y } ) =/= ( N ` { T } ) ) | 
						
							| 24 |  | mapdh8e.e |  |-  ( ph -> X e. ( N ` { Y , T } ) ) | 
						
							| 25 | 18 | eldifad |  |-  ( ph -> X e. V ) | 
						
							| 26 | 19 | eldifad |  |-  ( ph -> Y e. V ) | 
						
							| 27 | 1 2 3 6 14 25 26 | dvh3dim |  |-  ( ph -> E. w e. V -. w e. ( N ` { X , Y } ) ) | 
						
							| 28 | 14 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( K e. HL /\ W e. H ) ) | 
						
							| 29 | 15 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> F e. D ) | 
						
							| 30 | 16 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( M ` ( N ` { X } ) ) = ( J ` { F } ) ) | 
						
							| 31 | 17 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( I ` <. X , F , Y >. ) = G ) | 
						
							| 32 | 18 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> X e. ( V \ { .0. } ) ) | 
						
							| 33 | 19 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> Y e. ( V \ { .0. } ) ) | 
						
							| 34 | 20 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> T e. ( V \ { .0. } ) ) | 
						
							| 35 | 23 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { Y } ) =/= ( N ` { T } ) ) | 
						
							| 36 |  | eqid |  |-  ( LSubSp ` U ) = ( LSubSp ` U ) | 
						
							| 37 | 1 2 14 | dvhlmod |  |-  ( ph -> U e. LMod ) | 
						
							| 38 | 37 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> U e. LMod ) | 
						
							| 39 | 3 36 6 37 25 26 | lspprcl |  |-  ( ph -> ( N ` { X , Y } ) e. ( LSubSp ` U ) ) | 
						
							| 40 | 39 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { X , Y } ) e. ( LSubSp ` U ) ) | 
						
							| 41 |  | simp2 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> w e. V ) | 
						
							| 42 |  | simp3 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> -. w e. ( N ` { X , Y } ) ) | 
						
							| 43 | 5 36 38 40 41 42 | lssneln0 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> w e. ( V \ { .0. } ) ) | 
						
							| 44 | 1 2 14 | dvhlvec |  |-  ( ph -> U e. LVec ) | 
						
							| 45 | 20 | eldifad |  |-  ( ph -> T e. V ) | 
						
							| 46 |  | prcom |  |-  { Y , T } = { T , Y } | 
						
							| 47 | 46 | fveq2i |  |-  ( N ` { Y , T } ) = ( N ` { T , Y } ) | 
						
							| 48 | 24 47 | eleqtrdi |  |-  ( ph -> X e. ( N ` { T , Y } ) ) | 
						
							| 49 | 3 5 6 44 18 45 26 21 48 | lspexch |  |-  ( ph -> T e. ( N ` { X , Y } ) ) | 
						
							| 50 | 36 6 37 39 49 | ellspsn5 |  |-  ( ph -> ( N ` { T } ) C_ ( N ` { X , Y } ) ) | 
						
							| 51 | 50 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { T } ) C_ ( N ` { X , Y } ) ) | 
						
							| 52 | 37 | adantr |  |-  ( ( ph /\ w e. V ) -> U e. LMod ) | 
						
							| 53 | 39 | adantr |  |-  ( ( ph /\ w e. V ) -> ( N ` { X , Y } ) e. ( LSubSp ` U ) ) | 
						
							| 54 |  | simpr |  |-  ( ( ph /\ w e. V ) -> w e. V ) | 
						
							| 55 | 3 36 6 52 53 54 | ellspsn5b |  |-  ( ( ph /\ w e. V ) -> ( w e. ( N ` { X , Y } ) <-> ( N ` { w } ) C_ ( N ` { X , Y } ) ) ) | 
						
							| 56 | 55 | biimprd |  |-  ( ( ph /\ w e. V ) -> ( ( N ` { w } ) C_ ( N ` { X , Y } ) -> w e. ( N ` { X , Y } ) ) ) | 
						
							| 57 | 56 | con3d |  |-  ( ( ph /\ w e. V ) -> ( -. w e. ( N ` { X , Y } ) -> -. ( N ` { w } ) C_ ( N ` { X , Y } ) ) ) | 
						
							| 58 | 57 | 3impia |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> -. ( N ` { w } ) C_ ( N ` { X , Y } ) ) | 
						
							| 59 |  | nssne2 |  |-  ( ( ( N ` { T } ) C_ ( N ` { X , Y } ) /\ -. ( N ` { w } ) C_ ( N ` { X , Y } ) ) -> ( N ` { T } ) =/= ( N ` { w } ) ) | 
						
							| 60 | 51 58 59 | syl2anc |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { T } ) =/= ( N ` { w } ) ) | 
						
							| 61 | 60 | necomd |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { w } ) =/= ( N ` { T } ) ) | 
						
							| 62 | 22 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { X } ) =/= ( N ` { T } ) ) | 
						
							| 63 | 44 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> U e. LVec ) | 
						
							| 64 | 25 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> X e. V ) | 
						
							| 65 | 26 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> Y e. V ) | 
						
							| 66 | 3 6 63 41 64 65 42 | lspindpi |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( ( N ` { w } ) =/= ( N ` { X } ) /\ ( N ` { w } ) =/= ( N ` { Y } ) ) ) | 
						
							| 67 | 66 | simprd |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { w } ) =/= ( N ` { Y } ) ) | 
						
							| 68 | 67 | necomd |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { Y } ) =/= ( N ` { w } ) ) | 
						
							| 69 | 21 | 3ad2ant1 |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( N ` { X } ) =/= ( N ` { Y } ) ) | 
						
							| 70 | 3 5 6 63 32 65 41 69 42 | lspindp2l |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( ( N ` { Y } ) =/= ( N ` { w } ) /\ -. X e. ( N ` { Y , w } ) ) ) | 
						
							| 71 | 70 | simprd |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> -. X e. ( N ` { Y , w } ) ) | 
						
							| 72 | 1 2 3 4 5 6 7 8 9 10 11 12 13 28 29 30 31 32 33 34 35 43 61 62 68 71 | mapdh8d |  |-  ( ( ph /\ w e. V /\ -. w e. ( N ` { X , Y } ) ) -> ( I ` <. Y , G , T >. ) = ( I ` <. X , F , T >. ) ) | 
						
							| 73 | 72 | rexlimdv3a |  |-  ( ph -> ( E. w e. V -. w e. ( N ` { X , Y } ) -> ( I ` <. Y , G , T >. ) = ( I ` <. X , F , T >. ) ) ) | 
						
							| 74 | 27 73 | mpd |  |-  ( ph -> ( I ` <. Y , G , T >. ) = ( I ` <. X , F , T >. ) ) |