Metamath Proof Explorer


Theorem lclkrlem2q

Description: Lemma for lclkr . The sum has a closed kernel when B is nonzero. (Contributed by NM, 18-Jan-2015)

Ref Expression
Hypotheses lclkrlem2m.v
|- V = ( Base ` U )
lclkrlem2m.t
|- .x. = ( .s ` U )
lclkrlem2m.s
|- S = ( Scalar ` U )
lclkrlem2m.q
|- .X. = ( .r ` S )
lclkrlem2m.z
|- .0. = ( 0g ` S )
lclkrlem2m.i
|- I = ( invr ` S )
lclkrlem2m.m
|- .- = ( -g ` U )
lclkrlem2m.f
|- F = ( LFnl ` U )
lclkrlem2m.d
|- D = ( LDual ` U )
lclkrlem2m.p
|- .+ = ( +g ` D )
lclkrlem2m.x
|- ( ph -> X e. V )
lclkrlem2m.y
|- ( ph -> Y e. V )
lclkrlem2m.e
|- ( ph -> E e. F )
lclkrlem2m.g
|- ( ph -> G e. F )
lclkrlem2n.n
|- N = ( LSpan ` U )
lclkrlem2n.l
|- L = ( LKer ` U )
lclkrlem2o.h
|- H = ( LHyp ` K )
lclkrlem2o.o
|- ._|_ = ( ( ocH ` K ) ` W )
lclkrlem2o.u
|- U = ( ( DVecH ` K ) ` W )
lclkrlem2o.a
|- .(+) = ( LSSum ` U )
lclkrlem2o.k
|- ( ph -> ( K e. HL /\ W e. H ) )
lclkrlem2q.le
|- ( ph -> ( L ` E ) = ( ._|_ ` { X } ) )
lclkrlem2q.lg
|- ( ph -> ( L ` G ) = ( ._|_ ` { Y } ) )
lclkrlem2q.b
|- B = ( X .- ( ( ( ( E .+ G ) ` X ) .X. ( I ` ( ( E .+ G ) ` Y ) ) ) .x. Y ) )
lclkrlem2q.n
|- ( ph -> ( ( E .+ G ) ` Y ) =/= .0. )
lclkrlem2q.bn
|- ( ph -> B =/= ( 0g ` U ) )
Assertion lclkrlem2q
|- ( ph -> ( ._|_ ` ( ._|_ ` ( L ` ( E .+ G ) ) ) ) = ( L ` ( E .+ G ) ) )

Proof

Step Hyp Ref Expression
1 lclkrlem2m.v
 |-  V = ( Base ` U )
2 lclkrlem2m.t
 |-  .x. = ( .s ` U )
3 lclkrlem2m.s
 |-  S = ( Scalar ` U )
4 lclkrlem2m.q
 |-  .X. = ( .r ` S )
5 lclkrlem2m.z
 |-  .0. = ( 0g ` S )
6 lclkrlem2m.i
 |-  I = ( invr ` S )
7 lclkrlem2m.m
 |-  .- = ( -g ` U )
8 lclkrlem2m.f
 |-  F = ( LFnl ` U )
9 lclkrlem2m.d
 |-  D = ( LDual ` U )
10 lclkrlem2m.p
 |-  .+ = ( +g ` D )
11 lclkrlem2m.x
 |-  ( ph -> X e. V )
12 lclkrlem2m.y
 |-  ( ph -> Y e. V )
13 lclkrlem2m.e
 |-  ( ph -> E e. F )
14 lclkrlem2m.g
 |-  ( ph -> G e. F )
15 lclkrlem2n.n
 |-  N = ( LSpan ` U )
16 lclkrlem2n.l
 |-  L = ( LKer ` U )
17 lclkrlem2o.h
 |-  H = ( LHyp ` K )
18 lclkrlem2o.o
 |-  ._|_ = ( ( ocH ` K ) ` W )
19 lclkrlem2o.u
 |-  U = ( ( DVecH ` K ) ` W )
20 lclkrlem2o.a
 |-  .(+) = ( LSSum ` U )
21 lclkrlem2o.k
 |-  ( ph -> ( K e. HL /\ W e. H ) )
22 lclkrlem2q.le
 |-  ( ph -> ( L ` E ) = ( ._|_ ` { X } ) )
23 lclkrlem2q.lg
 |-  ( ph -> ( L ` G ) = ( ._|_ ` { Y } ) )
24 lclkrlem2q.b
 |-  B = ( X .- ( ( ( ( E .+ G ) ` X ) .X. ( I ` ( ( E .+ G ) ` Y ) ) ) .x. Y ) )
25 lclkrlem2q.n
 |-  ( ph -> ( ( E .+ G ) ` Y ) =/= .0. )
26 lclkrlem2q.bn
 |-  ( ph -> B =/= ( 0g ` U ) )
27 eqid
 |-  ( 0g ` U ) = ( 0g ` U )
28 eqid
 |-  ( LSHyp ` U ) = ( LSHyp ` U )
29 17 19 21 dvhlvec
 |-  ( ph -> U e. LVec )
30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 29 24 25 lclkrlem2m
 |-  ( ph -> ( B e. V /\ ( ( E .+ G ) ` B ) = .0. ) )
31 30 simpld
 |-  ( ph -> B e. V )
32 eldifsn
 |-  ( B e. ( V \ { ( 0g ` U ) } ) <-> ( B e. V /\ B =/= ( 0g ` U ) ) )
33 31 26 32 sylanbrc
 |-  ( ph -> B e. ( V \ { ( 0g ` U ) } ) )
34 30 simprd
 |-  ( ph -> ( ( E .+ G ) ` B ) = .0. )
35 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 24 25 26 lclkrlem2o
 |-  ( ph -> ( -. X e. ( ._|_ ` { B } ) \/ -. Y e. ( ._|_ ` { B } ) ) )
36 17 18 19 1 3 5 27 20 15 8 28 16 9 10 21 33 13 14 22 23 34 35 11 12 lclkrlem2l
 |-  ( ph -> ( ._|_ ` ( ._|_ ` ( L ` ( E .+ G ) ) ) ) = ( L ` ( E .+ G ) ) )