Metamath Proof Explorer


Theorem mapdh8

Description: Part (8) in Baer p. 48. Given a reference vector X , the value of function I at a vector T is independent of the choice of auxiliary vectors Y and Z . Unlike Baer's, our version does not require X , Y , and Z to be independent, and also is defined for all Y and Z that are not colinear with X or T . We do this to make the definition of Baer's sigma function more straightforward. (This part eliminates T =/= .0. .) (Contributed by NM, 13-May-2015)

Ref Expression
Hypotheses mapdh8a.h
|- H = ( LHyp ` K )
mapdh8a.u
|- U = ( ( DVecH ` K ) ` W )
mapdh8a.v
|- V = ( Base ` U )
mapdh8a.s
|- .- = ( -g ` U )
mapdh8a.o
|- .0. = ( 0g ` U )
mapdh8a.n
|- N = ( LSpan ` U )
mapdh8a.c
|- C = ( ( LCDual ` K ) ` W )
mapdh8a.d
|- D = ( Base ` C )
mapdh8a.r
|- R = ( -g ` C )
mapdh8a.q
|- Q = ( 0g ` C )
mapdh8a.j
|- J = ( LSpan ` C )
mapdh8a.m
|- M = ( ( mapd ` K ) ` W )
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 ) } ) ) ) ) )
mapdh8a.k
|- ( ph -> ( K e. HL /\ W e. H ) )
mapdh8h.f
|- ( ph -> F e. D )
mapdh8h.mn
|- ( ph -> ( M ` ( N ` { X } ) ) = ( J ` { F } ) )
mapdh8i.x
|- ( ph -> X e. ( V \ { .0. } ) )
mapdh8i.y
|- ( ph -> Y e. ( V \ { .0. } ) )
mapdh8i.z
|- ( ph -> Z e. ( V \ { .0. } ) )
mapdh8i.xy
|- ( ph -> ( N ` { X } ) =/= ( N ` { Y } ) )
mapdh8i.xz
|- ( ph -> ( N ` { X } ) =/= ( N ` { Z } ) )
mapdh8i.yt
|- ( ph -> ( N ` { Y } ) =/= ( N ` { T } ) )
mapdh8i.zt
|- ( ph -> ( N ` { Z } ) =/= ( N ` { T } ) )
mapdh8.t
|- ( ph -> T e. V )
Assertion mapdh8
|- ( ph -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , T >. ) = ( I ` <. Z , ( I ` <. X , F , Z >. ) , T >. ) )

Proof

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 mapdh8h.f
 |-  ( ph -> F e. D )
16 mapdh8h.mn
 |-  ( ph -> ( M ` ( N ` { X } ) ) = ( J ` { F } ) )
17 mapdh8i.x
 |-  ( ph -> X e. ( V \ { .0. } ) )
18 mapdh8i.y
 |-  ( ph -> Y e. ( V \ { .0. } ) )
19 mapdh8i.z
 |-  ( ph -> Z e. ( V \ { .0. } ) )
20 mapdh8i.xy
 |-  ( ph -> ( N ` { X } ) =/= ( N ` { Y } ) )
21 mapdh8i.xz
 |-  ( ph -> ( N ` { X } ) =/= ( N ` { Z } ) )
22 mapdh8i.yt
 |-  ( ph -> ( N ` { Y } ) =/= ( N ` { T } ) )
23 mapdh8i.zt
 |-  ( ph -> ( N ` { Z } ) =/= ( N ` { T } ) )
24 mapdh8.t
 |-  ( ph -> T e. V )
25 fvexd
 |-  ( ph -> ( I ` <. X , F , Y >. ) e. _V )
26 10 13 5 18 25 mapdhval0
 |-  ( ph -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , .0. >. ) = Q )
27 fvexd
 |-  ( ph -> ( I ` <. X , F , Z >. ) e. _V )
28 10 13 5 19 27 mapdhval0
 |-  ( ph -> ( I ` <. Z , ( I ` <. X , F , Z >. ) , .0. >. ) = Q )
29 26 28 eqtr4d
 |-  ( ph -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , .0. >. ) = ( I ` <. Z , ( I ` <. X , F , Z >. ) , .0. >. ) )
30 29 adantr
 |-  ( ( ph /\ T = .0. ) -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , .0. >. ) = ( I ` <. Z , ( I ` <. X , F , Z >. ) , .0. >. ) )
31 oteq3
 |-  ( T = .0. -> <. Y , ( I ` <. X , F , Y >. ) , T >. = <. Y , ( I ` <. X , F , Y >. ) , .0. >. )
32 31 fveq2d
 |-  ( T = .0. -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , T >. ) = ( I ` <. Y , ( I ` <. X , F , Y >. ) , .0. >. ) )
33 32 adantl
 |-  ( ( ph /\ T = .0. ) -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , T >. ) = ( I ` <. Y , ( I ` <. X , F , Y >. ) , .0. >. ) )
34 oteq3
 |-  ( T = .0. -> <. Z , ( I ` <. X , F , Z >. ) , T >. = <. Z , ( I ` <. X , F , Z >. ) , .0. >. )
35 34 fveq2d
 |-  ( T = .0. -> ( I ` <. Z , ( I ` <. X , F , Z >. ) , T >. ) = ( I ` <. Z , ( I ` <. X , F , Z >. ) , .0. >. ) )
36 35 adantl
 |-  ( ( ph /\ T = .0. ) -> ( I ` <. Z , ( I ` <. X , F , Z >. ) , T >. ) = ( I ` <. Z , ( I ` <. X , F , Z >. ) , .0. >. ) )
37 30 33 36 3eqtr4d
 |-  ( ( ph /\ T = .0. ) -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , T >. ) = ( I ` <. Z , ( I ` <. X , F , Z >. ) , T >. ) )
38 14 adantr
 |-  ( ( ph /\ T =/= .0. ) -> ( K e. HL /\ W e. H ) )
39 15 adantr
 |-  ( ( ph /\ T =/= .0. ) -> F e. D )
40 16 adantr
 |-  ( ( ph /\ T =/= .0. ) -> ( M ` ( N ` { X } ) ) = ( J ` { F } ) )
41 17 adantr
 |-  ( ( ph /\ T =/= .0. ) -> X e. ( V \ { .0. } ) )
42 18 adantr
 |-  ( ( ph /\ T =/= .0. ) -> Y e. ( V \ { .0. } ) )
43 19 adantr
 |-  ( ( ph /\ T =/= .0. ) -> Z e. ( V \ { .0. } ) )
44 20 adantr
 |-  ( ( ph /\ T =/= .0. ) -> ( N ` { X } ) =/= ( N ` { Y } ) )
45 21 adantr
 |-  ( ( ph /\ T =/= .0. ) -> ( N ` { X } ) =/= ( N ` { Z } ) )
46 22 adantr
 |-  ( ( ph /\ T =/= .0. ) -> ( N ` { Y } ) =/= ( N ` { T } ) )
47 23 adantr
 |-  ( ( ph /\ T =/= .0. ) -> ( N ` { Z } ) =/= ( N ` { T } ) )
48 24 anim1i
 |-  ( ( ph /\ T =/= .0. ) -> ( T e. V /\ T =/= .0. ) )
49 eldifsn
 |-  ( T e. ( V \ { .0. } ) <-> ( T e. V /\ T =/= .0. ) )
50 48 49 sylibr
 |-  ( ( ph /\ T =/= .0. ) -> T e. ( V \ { .0. } ) )
51 1 2 3 4 5 6 7 8 9 10 11 12 13 38 39 40 41 42 43 44 45 46 47 50 mapdh8j
 |-  ( ( ph /\ T =/= .0. ) -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , T >. ) = ( I ` <. Z , ( I ` <. X , F , Z >. ) , T >. ) )
52 37 51 pm2.61dane
 |-  ( ph -> ( I ` <. Y , ( I ` <. X , F , Y >. ) , T >. ) = ( I ` <. Z , ( I ` <. X , F , Z >. ) , T >. ) )