Metamath Proof Explorer


Theorem strlem1

Description: Lemma for strong state theorem: if closed subspace A is not contained in B , there is a unit vector u in their difference. (Contributed by NM, 25-Oct-1999) (New usage is discouraged.)

Ref Expression
Hypotheses strlem1.1 AC
strlem1.2 BC
Assertion strlem1 ¬ABuABnormu=1

Proof

Step Hyp Ref Expression
1 strlem1.1 AC
2 strlem1.2 BC
3 neq0 ¬AB=xxAB
4 ssdif0 ABAB=
5 3 4 xchnxbir ¬ABxxAB
6 eldifi xABxA
7 1 cheli xAx
8 normcl xnormx
9 6 7 8 3syl xABnormx
10 ch0 BC0B
11 2 10 ax-mp 0B
12 eldifn 0AB¬0B
13 11 12 mt2 ¬0AB
14 eleq1 x=0xAB0AB
15 13 14 mtbiri x=0¬xAB
16 15 con2i xAB¬x=0
17 norm-i xnormx=0x=0
18 6 7 17 3syl xABnormx=0x=0
19 16 18 mtbird xAB¬normx=0
20 19 neqned xABnormx0
21 9 20 rereccld xAB1normx
22 21 recnd xAB1normx
23 1 chshii AS
24 shmulcl AS1normxxA1normxxA
25 23 24 mp3an1 1normxxA1normxxA
26 25 ex 1normxxA1normxxA
27 22 26 syl xABxA1normxxA
28 9 recnd xABnormx
29 2 chshii BS
30 shmulcl BSnormx1normxxBnormx1normxxB
31 29 30 mp3an1 normx1normxxBnormx1normxxB
32 31 ex normx1normxxBnormx1normxxB
33 28 32 syl xAB1normxxBnormx1normxxB
34 28 20 recidd xABnormx1normx=1
35 34 oveq1d xABnormx1normxx=1x
36 6 7 syl xABx
37 ax-hvmulass normx1normxxnormx1normxx=normx1normxx
38 28 22 36 37 syl3anc xABnormx1normxx=normx1normxx
39 ax-hvmulid x1x=x
40 6 7 39 3syl xAB1x=x
41 35 38 40 3eqtr3d xABnormx1normxx=x
42 41 eleq1d xABnormx1normxxBxB
43 33 42 sylibd xAB1normxxBxB
44 43 con3d xAB¬xB¬1normxxB
45 27 44 anim12d xABxA¬xB1normxxA¬1normxxB
46 eldif xABxA¬xB
47 eldif 1normxxAB1normxxA¬1normxxB
48 45 46 47 3imtr4g xABxAB1normxxAB
49 48 pm2.43i xAB1normxxAB
50 norm-iii 1normxxnorm1normxx=1normxnormx
51 22 36 50 syl2anc xABnorm1normxx=1normxnormx
52 15 necon2ai xABx0
53 normgt0 xx00<normx
54 6 7 53 3syl xABx00<normx
55 52 54 mpbid xAB0<normx
56 1re 1
57 0le1 01
58 divge0 101normx0<normx01normx
59 56 57 58 mpanl12 normx0<normx01normx
60 9 55 59 syl2anc xAB01normx
61 21 60 absidd xAB1normx=1normx
62 61 oveq1d xAB1normxnormx=1normxnormx
63 28 20 recid2d xAB1normxnormx=1
64 51 62 63 3eqtrd xABnorm1normxx=1
65 fveqeq2 u=1normxxnormu=1norm1normxx=1
66 65 rspcev 1normxxABnorm1normxx=1uABnormu=1
67 49 64 66 syl2anc xABuABnormu=1
68 67 exlimiv xxABuABnormu=1
69 5 68 sylbi ¬ABuABnormu=1