| Step | Hyp | Ref | Expression | 
						
							| 1 |  | baerlem3.v |  |-  V = ( Base ` W ) | 
						
							| 2 |  | baerlem3.m |  |-  .- = ( -g ` W ) | 
						
							| 3 |  | baerlem3.o |  |-  .0. = ( 0g ` W ) | 
						
							| 4 |  | baerlem3.s |  |-  .(+) = ( LSSum ` W ) | 
						
							| 5 |  | baerlem3.n |  |-  N = ( LSpan ` W ) | 
						
							| 6 |  | baerlem3.w |  |-  ( ph -> W e. LVec ) | 
						
							| 7 |  | baerlem3.x |  |-  ( ph -> X e. V ) | 
						
							| 8 |  | baerlem3.c |  |-  ( ph -> -. X e. ( N ` { Y , Z } ) ) | 
						
							| 9 |  | baerlem3.d |  |-  ( ph -> ( N ` { Y } ) =/= ( N ` { Z } ) ) | 
						
							| 10 |  | baerlem3.y |  |-  ( ph -> Y e. ( V \ { .0. } ) ) | 
						
							| 11 |  | baerlem3.z |  |-  ( ph -> Z e. ( V \ { .0. } ) ) | 
						
							| 12 |  | baerlem5a.p |  |-  .+ = ( +g ` W ) | 
						
							| 13 | 10 | eldifad |  |-  ( ph -> Y e. V ) | 
						
							| 14 | 11 | eldifad |  |-  ( ph -> Z e. V ) | 
						
							| 15 |  | eqid |  |-  ( invg ` W ) = ( invg ` W ) | 
						
							| 16 | 1 12 15 2 | grpsubval |  |-  ( ( Y e. V /\ Z e. V ) -> ( Y .- Z ) = ( Y .+ ( ( invg ` W ) ` Z ) ) ) | 
						
							| 17 | 13 14 16 | syl2anc |  |-  ( ph -> ( Y .- Z ) = ( Y .+ ( ( invg ` W ) ` Z ) ) ) | 
						
							| 18 | 17 | sneqd |  |-  ( ph -> { ( Y .- Z ) } = { ( Y .+ ( ( invg ` W ) ` Z ) ) } ) | 
						
							| 19 | 18 | fveq2d |  |-  ( ph -> ( N ` { ( Y .- Z ) } ) = ( N ` { ( Y .+ ( ( invg ` W ) ` Z ) ) } ) ) | 
						
							| 20 |  | lveclmod |  |-  ( W e. LVec -> W e. LMod ) | 
						
							| 21 | 6 20 | syl |  |-  ( ph -> W e. LMod ) | 
						
							| 22 | 1 15 | lmodvnegcl |  |-  ( ( W e. LMod /\ Z e. V ) -> ( ( invg ` W ) ` Z ) e. V ) | 
						
							| 23 | 21 14 22 | syl2anc |  |-  ( ph -> ( ( invg ` W ) ` Z ) e. V ) | 
						
							| 24 |  | eqid |  |-  ( LSubSp ` W ) = ( LSubSp ` W ) | 
						
							| 25 | 1 24 5 21 13 14 | lspprcl |  |-  ( ph -> ( N ` { Y , Z } ) e. ( LSubSp ` W ) ) | 
						
							| 26 | 3 24 21 25 7 8 | lssneln0 |  |-  ( ph -> X e. ( V \ { .0. } ) ) | 
						
							| 27 | 1 5 6 7 13 14 8 | lspindpi |  |-  ( ph -> ( ( N ` { X } ) =/= ( N ` { Y } ) /\ ( N ` { X } ) =/= ( N ` { Z } ) ) ) | 
						
							| 28 | 27 | simpld |  |-  ( ph -> ( N ` { X } ) =/= ( N ` { Y } ) ) | 
						
							| 29 | 1 3 5 6 26 13 28 | lspsnne1 |  |-  ( ph -> -. X e. ( N ` { Y } ) ) | 
						
							| 30 | 9 | necomd |  |-  ( ph -> ( N ` { Z } ) =/= ( N ` { Y } ) ) | 
						
							| 31 | 1 3 5 6 11 13 30 | lspsnne1 |  |-  ( ph -> -. Z e. ( N ` { Y } ) ) | 
						
							| 32 | 1 5 6 7 14 13 31 8 | lspexchn2 |  |-  ( ph -> -. Z e. ( N ` { Y , X } ) ) | 
						
							| 33 |  | lmodgrp |  |-  ( W e. LMod -> W e. Grp ) | 
						
							| 34 | 21 33 | syl |  |-  ( ph -> W e. Grp ) | 
						
							| 35 | 34 | adantr |  |-  ( ( ph /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> W e. Grp ) | 
						
							| 36 | 14 | adantr |  |-  ( ( ph /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> Z e. V ) | 
						
							| 37 | 1 15 | grpinvinv |  |-  ( ( W e. Grp /\ Z e. V ) -> ( ( invg ` W ) ` ( ( invg ` W ) ` Z ) ) = Z ) | 
						
							| 38 | 35 36 37 | syl2anc |  |-  ( ( ph /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> ( ( invg ` W ) ` ( ( invg ` W ) ` Z ) ) = Z ) | 
						
							| 39 | 21 | adantr |  |-  ( ( ph /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> W e. LMod ) | 
						
							| 40 | 1 24 5 21 13 7 | lspprcl |  |-  ( ph -> ( N ` { Y , X } ) e. ( LSubSp ` W ) ) | 
						
							| 41 | 40 | adantr |  |-  ( ( ph /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> ( N ` { Y , X } ) e. ( LSubSp ` W ) ) | 
						
							| 42 |  | simpr |  |-  ( ( ph /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) | 
						
							| 43 | 24 15 | lssvnegcl |  |-  ( ( W e. LMod /\ ( N ` { Y , X } ) e. ( LSubSp ` W ) /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> ( ( invg ` W ) ` ( ( invg ` W ) ` Z ) ) e. ( N ` { Y , X } ) ) | 
						
							| 44 | 39 41 42 43 | syl3anc |  |-  ( ( ph /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> ( ( invg ` W ) ` ( ( invg ` W ) ` Z ) ) e. ( N ` { Y , X } ) ) | 
						
							| 45 | 38 44 | eqeltrrd |  |-  ( ( ph /\ ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) -> Z e. ( N ` { Y , X } ) ) | 
						
							| 46 | 32 45 | mtand |  |-  ( ph -> -. ( ( invg ` W ) ` Z ) e. ( N ` { Y , X } ) ) | 
						
							| 47 | 1 5 6 23 7 13 29 46 | lspexchn2 |  |-  ( ph -> -. X e. ( N ` { Y , ( ( invg ` W ) ` Z ) } ) ) | 
						
							| 48 | 1 15 5 | lspsnneg |  |-  ( ( W e. LMod /\ Z e. V ) -> ( N ` { ( ( invg ` W ) ` Z ) } ) = ( N ` { Z } ) ) | 
						
							| 49 | 21 14 48 | syl2anc |  |-  ( ph -> ( N ` { ( ( invg ` W ) ` Z ) } ) = ( N ` { Z } ) ) | 
						
							| 50 | 9 49 | neeqtrrd |  |-  ( ph -> ( N ` { Y } ) =/= ( N ` { ( ( invg ` W ) ` Z ) } ) ) | 
						
							| 51 | 1 3 15 | grpinvnzcl |  |-  ( ( W e. Grp /\ Z e. ( V \ { .0. } ) ) -> ( ( invg ` W ) ` Z ) e. ( V \ { .0. } ) ) | 
						
							| 52 | 34 11 51 | syl2anc |  |-  ( ph -> ( ( invg ` W ) ` Z ) e. ( V \ { .0. } ) ) | 
						
							| 53 | 1 2 3 4 5 6 7 47 50 10 52 12 | baerlem5b |  |-  ( ph -> ( N ` { ( Y .+ ( ( invg ` W ) ` Z ) ) } ) = ( ( ( N ` { Y } ) .(+) ( N ` { ( ( invg ` W ) ` Z ) } ) ) i^i ( ( N ` { ( X .- ( Y .+ ( ( invg ` W ) ` Z ) ) ) } ) .(+) ( N ` { X } ) ) ) ) | 
						
							| 54 | 49 | oveq2d |  |-  ( ph -> ( ( N ` { Y } ) .(+) ( N ` { ( ( invg ` W ) ` Z ) } ) ) = ( ( N ` { Y } ) .(+) ( N ` { Z } ) ) ) | 
						
							| 55 | 17 | eqcomd |  |-  ( ph -> ( Y .+ ( ( invg ` W ) ` Z ) ) = ( Y .- Z ) ) | 
						
							| 56 | 55 | oveq2d |  |-  ( ph -> ( X .- ( Y .+ ( ( invg ` W ) ` Z ) ) ) = ( X .- ( Y .- Z ) ) ) | 
						
							| 57 | 56 | sneqd |  |-  ( ph -> { ( X .- ( Y .+ ( ( invg ` W ) ` Z ) ) ) } = { ( X .- ( Y .- Z ) ) } ) | 
						
							| 58 | 57 | fveq2d |  |-  ( ph -> ( N ` { ( X .- ( Y .+ ( ( invg ` W ) ` Z ) ) ) } ) = ( N ` { ( X .- ( Y .- Z ) ) } ) ) | 
						
							| 59 | 58 | oveq1d |  |-  ( ph -> ( ( N ` { ( X .- ( Y .+ ( ( invg ` W ) ` Z ) ) ) } ) .(+) ( N ` { X } ) ) = ( ( N ` { ( X .- ( Y .- Z ) ) } ) .(+) ( N ` { X } ) ) ) | 
						
							| 60 | 54 59 | ineq12d |  |-  ( ph -> ( ( ( N ` { Y } ) .(+) ( N ` { ( ( invg ` W ) ` Z ) } ) ) i^i ( ( N ` { ( X .- ( Y .+ ( ( invg ` W ) ` Z ) ) ) } ) .(+) ( N ` { X } ) ) ) = ( ( ( N ` { Y } ) .(+) ( N ` { Z } ) ) i^i ( ( N ` { ( X .- ( Y .- Z ) ) } ) .(+) ( N ` { X } ) ) ) ) | 
						
							| 61 | 19 53 60 | 3eqtrd |  |-  ( ph -> ( N ` { ( Y .- Z ) } ) = ( ( ( N ` { Y } ) .(+) ( N ` { Z } ) ) i^i ( ( N ` { ( X .- ( Y .- Z ) ) } ) .(+) ( N ` { X } ) ) ) ) |