| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mapdindp1.v |  |-  V = ( Base ` W ) | 
						
							| 2 |  | mapdindp1.p |  |-  .+ = ( +g ` W ) | 
						
							| 3 |  | mapdindp1.o |  |-  .0. = ( 0g ` W ) | 
						
							| 4 |  | mapdindp1.n |  |-  N = ( LSpan ` W ) | 
						
							| 5 |  | mapdindp1.w |  |-  ( ph -> W e. LVec ) | 
						
							| 6 |  | mapdindp1.x |  |-  ( ph -> X e. ( V \ { .0. } ) ) | 
						
							| 7 |  | mapdindp1.y |  |-  ( ph -> Y e. ( V \ { .0. } ) ) | 
						
							| 8 |  | mapdindp1.z |  |-  ( ph -> Z e. ( V \ { .0. } ) ) | 
						
							| 9 |  | mapdindp1.W |  |-  ( ph -> w e. ( V \ { .0. } ) ) | 
						
							| 10 |  | mapdindp1.e |  |-  ( ph -> ( N ` { Y } ) = ( N ` { Z } ) ) | 
						
							| 11 |  | mapdindp1.ne |  |-  ( ph -> ( N ` { X } ) =/= ( N ` { Y } ) ) | 
						
							| 12 |  | mapdindp1.f |  |-  ( ph -> -. w e. ( N ` { X , Y } ) ) | 
						
							| 13 |  | lveclmod |  |-  ( W e. LVec -> W e. LMod ) | 
						
							| 14 | 5 13 | syl |  |-  ( ph -> W e. LMod ) | 
						
							| 15 | 9 | eldifad |  |-  ( ph -> w e. V ) | 
						
							| 16 | 7 | eldifad |  |-  ( ph -> Y e. V ) | 
						
							| 17 | 1 2 | lmodvacl |  |-  ( ( W e. LMod /\ w e. V /\ Y e. V ) -> ( w .+ Y ) e. V ) | 
						
							| 18 | 14 15 16 17 | syl3anc |  |-  ( ph -> ( w .+ Y ) e. V ) | 
						
							| 19 | 6 | eldifad |  |-  ( ph -> X e. V ) | 
						
							| 20 | 1 4 5 15 19 16 12 | lspindpi |  |-  ( ph -> ( ( N ` { w } ) =/= ( N ` { X } ) /\ ( N ` { w } ) =/= ( N ` { Y } ) ) ) | 
						
							| 21 | 20 | simprd |  |-  ( ph -> ( N ` { w } ) =/= ( N ` { Y } ) ) | 
						
							| 22 | 21 | necomd |  |-  ( ph -> ( N ` { Y } ) =/= ( N ` { w } ) ) | 
						
							| 23 | 1 2 3 4 5 16 9 22 | lspindp3 |  |-  ( ph -> ( N ` { Y } ) =/= ( N ` { ( Y .+ w ) } ) ) | 
						
							| 24 | 1 2 | lmodcom |  |-  ( ( W e. LMod /\ w e. V /\ Y e. V ) -> ( w .+ Y ) = ( Y .+ w ) ) | 
						
							| 25 | 14 15 16 24 | syl3anc |  |-  ( ph -> ( w .+ Y ) = ( Y .+ w ) ) | 
						
							| 26 | 25 | sneqd |  |-  ( ph -> { ( w .+ Y ) } = { ( Y .+ w ) } ) | 
						
							| 27 | 26 | fveq2d |  |-  ( ph -> ( N ` { ( w .+ Y ) } ) = ( N ` { ( Y .+ w ) } ) ) | 
						
							| 28 | 23 27 | neeqtrrd |  |-  ( ph -> ( N ` { Y } ) =/= ( N ` { ( w .+ Y ) } ) ) | 
						
							| 29 | 10 28 | eqnetrrd |  |-  ( ph -> ( N ` { Z } ) =/= ( N ` { ( w .+ Y ) } ) ) | 
						
							| 30 | 1 3 4 5 6 16 15 11 12 | lspindp1 |  |-  ( ph -> ( ( N ` { w } ) =/= ( N ` { Y } ) /\ -. X e. ( N ` { w , Y } ) ) ) | 
						
							| 31 | 30 | simprd |  |-  ( ph -> -. X e. ( N ` { w , Y } ) ) | 
						
							| 32 |  | eqid |  |-  ( LSSum ` W ) = ( LSSum ` W ) | 
						
							| 33 | 8 | eldifad |  |-  ( ph -> Z e. V ) | 
						
							| 34 | 1 4 32 14 33 18 | lsmpr |  |-  ( ph -> ( N ` { Z , ( w .+ Y ) } ) = ( ( N ` { Z } ) ( LSSum ` W ) ( N ` { ( w .+ Y ) } ) ) ) | 
						
							| 35 | 1 2 | lmodcom |  |-  ( ( W e. LMod /\ Y e. V /\ w e. V ) -> ( Y .+ w ) = ( w .+ Y ) ) | 
						
							| 36 | 14 16 15 35 | syl3anc |  |-  ( ph -> ( Y .+ w ) = ( w .+ Y ) ) | 
						
							| 37 | 36 | preq2d |  |-  ( ph -> { Y , ( Y .+ w ) } = { Y , ( w .+ Y ) } ) | 
						
							| 38 | 37 | fveq2d |  |-  ( ph -> ( N ` { Y , ( Y .+ w ) } ) = ( N ` { Y , ( w .+ Y ) } ) ) | 
						
							| 39 | 1 2 4 14 16 15 | lspprabs |  |-  ( ph -> ( N ` { Y , ( Y .+ w ) } ) = ( N ` { Y , w } ) ) | 
						
							| 40 | 1 4 32 14 16 18 | lsmpr |  |-  ( ph -> ( N ` { Y , ( w .+ Y ) } ) = ( ( N ` { Y } ) ( LSSum ` W ) ( N ` { ( w .+ Y ) } ) ) ) | 
						
							| 41 | 38 39 40 | 3eqtr3rd |  |-  ( ph -> ( ( N ` { Y } ) ( LSSum ` W ) ( N ` { ( w .+ Y ) } ) ) = ( N ` { Y , w } ) ) | 
						
							| 42 | 10 | oveq1d |  |-  ( ph -> ( ( N ` { Y } ) ( LSSum ` W ) ( N ` { ( w .+ Y ) } ) ) = ( ( N ` { Z } ) ( LSSum ` W ) ( N ` { ( w .+ Y ) } ) ) ) | 
						
							| 43 |  | prcom |  |-  { Y , w } = { w , Y } | 
						
							| 44 | 43 | fveq2i |  |-  ( N ` { Y , w } ) = ( N ` { w , Y } ) | 
						
							| 45 | 44 | a1i |  |-  ( ph -> ( N ` { Y , w } ) = ( N ` { w , Y } ) ) | 
						
							| 46 | 41 42 45 | 3eqtr3d |  |-  ( ph -> ( ( N ` { Z } ) ( LSSum ` W ) ( N ` { ( w .+ Y ) } ) ) = ( N ` { w , Y } ) ) | 
						
							| 47 | 34 46 | eqtrd |  |-  ( ph -> ( N ` { Z , ( w .+ Y ) } ) = ( N ` { w , Y } ) ) | 
						
							| 48 | 31 47 | neleqtrrd |  |-  ( ph -> -. X e. ( N ` { Z , ( w .+ Y ) } ) ) | 
						
							| 49 | 1 3 4 5 8 18 19 29 48 | lspindp1 |  |-  ( ph -> ( ( N ` { X } ) =/= ( N ` { ( w .+ Y ) } ) /\ -. Z e. ( N ` { X , ( w .+ Y ) } ) ) ) | 
						
							| 50 | 49 | simprd |  |-  ( ph -> -. Z e. ( N ` { X , ( w .+ Y ) } ) ) |