Metamath Proof Explorer


Theorem lspsncmp

Description: Comparable spans of nonzero singletons are equal. (Contributed by NM, 27-Apr-2015)

Ref Expression
Hypotheses lspsncmp.v
|- V = ( Base ` W )
lspsncmp.o
|- .0. = ( 0g ` W )
lspsncmp.n
|- N = ( LSpan ` W )
lspsncmp.w
|- ( ph -> W e. LVec )
lspsncmp.x
|- ( ph -> X e. ( V \ { .0. } ) )
lspsncmp.y
|- ( ph -> Y e. V )
Assertion lspsncmp
|- ( ph -> ( ( N ` { X } ) C_ ( N ` { Y } ) <-> ( N ` { X } ) = ( N ` { Y } ) ) )

Proof

Step Hyp Ref Expression
1 lspsncmp.v
 |-  V = ( Base ` W )
2 lspsncmp.o
 |-  .0. = ( 0g ` W )
3 lspsncmp.n
 |-  N = ( LSpan ` W )
4 lspsncmp.w
 |-  ( ph -> W e. LVec )
5 lspsncmp.x
 |-  ( ph -> X e. ( V \ { .0. } ) )
6 lspsncmp.y
 |-  ( ph -> Y e. V )
7 4 adantr
 |-  ( ( ph /\ ( N ` { X } ) C_ ( N ` { Y } ) ) -> W e. LVec )
8 6 adantr
 |-  ( ( ph /\ ( N ` { X } ) C_ ( N ` { Y } ) ) -> Y e. V )
9 eqid
 |-  ( LSubSp ` W ) = ( LSubSp ` W )
10 lveclmod
 |-  ( W e. LVec -> W e. LMod )
11 4 10 syl
 |-  ( ph -> W e. LMod )
12 1 9 3 lspsncl
 |-  ( ( W e. LMod /\ Y e. V ) -> ( N ` { Y } ) e. ( LSubSp ` W ) )
13 11 6 12 syl2anc
 |-  ( ph -> ( N ` { Y } ) e. ( LSubSp ` W ) )
14 5 eldifad
 |-  ( ph -> X e. V )
15 1 9 3 11 13 14 lspsnel5
 |-  ( ph -> ( X e. ( N ` { Y } ) <-> ( N ` { X } ) C_ ( N ` { Y } ) ) )
16 15 biimpar
 |-  ( ( ph /\ ( N ` { X } ) C_ ( N ` { Y } ) ) -> X e. ( N ` { Y } ) )
17 eldifsni
 |-  ( X e. ( V \ { .0. } ) -> X =/= .0. )
18 5 17 syl
 |-  ( ph -> X =/= .0. )
19 18 adantr
 |-  ( ( ph /\ ( N ` { X } ) C_ ( N ` { Y } ) ) -> X =/= .0. )
20 1 2 3 7 8 16 19 lspsneleq
 |-  ( ( ph /\ ( N ` { X } ) C_ ( N ` { Y } ) ) -> ( N ` { X } ) = ( N ` { Y } ) )
21 20 ex
 |-  ( ph -> ( ( N ` { X } ) C_ ( N ` { Y } ) -> ( N ` { X } ) = ( N ` { Y } ) ) )
22 eqimss
 |-  ( ( N ` { X } ) = ( N ` { Y } ) -> ( N ` { X } ) C_ ( N ` { Y } ) )
23 21 22 impbid1
 |-  ( ph -> ( ( N ` { X } ) C_ ( N ` { Y } ) <-> ( N ` { X } ) = ( N ` { Y } ) ) )