Step |
Hyp |
Ref |
Expression |
1 |
|
pjima.1 |
|- A e. SH |
2 |
|
pjima.2 |
|- B e. CH |
3 |
1
|
sheli |
|- ( v e. A -> v e. ~H ) |
4 |
|
pjeq |
|- ( ( B e. CH /\ v e. ~H ) -> ( ( ( projh ` B ) ` v ) = u <-> ( u e. B /\ E. w e. ( _|_ ` B ) v = ( u +h w ) ) ) ) |
5 |
2 3 4
|
sylancr |
|- ( v e. A -> ( ( ( projh ` B ) ` v ) = u <-> ( u e. B /\ E. w e. ( _|_ ` B ) v = ( u +h w ) ) ) ) |
6 |
|
ibar |
|- ( u e. B -> ( E. w e. ( _|_ ` B ) v = ( u +h w ) <-> ( u e. B /\ E. w e. ( _|_ ` B ) v = ( u +h w ) ) ) ) |
7 |
6
|
bicomd |
|- ( u e. B -> ( ( u e. B /\ E. w e. ( _|_ ` B ) v = ( u +h w ) ) <-> E. w e. ( _|_ ` B ) v = ( u +h w ) ) ) |
8 |
5 7
|
sylan9bbr |
|- ( ( u e. B /\ v e. A ) -> ( ( ( projh ` B ) ` v ) = u <-> E. w e. ( _|_ ` B ) v = ( u +h w ) ) ) |
9 |
2
|
cheli |
|- ( u e. B -> u e. ~H ) |
10 |
2
|
choccli |
|- ( _|_ ` B ) e. CH |
11 |
10
|
cheli |
|- ( w e. ( _|_ ` B ) -> w e. ~H ) |
12 |
|
hvsubadd |
|- ( ( v e. ~H /\ w e. ~H /\ u e. ~H ) -> ( ( v -h w ) = u <-> ( w +h u ) = v ) ) |
13 |
12
|
3comr |
|- ( ( u e. ~H /\ v e. ~H /\ w e. ~H ) -> ( ( v -h w ) = u <-> ( w +h u ) = v ) ) |
14 |
|
ax-hvcom |
|- ( ( u e. ~H /\ w e. ~H ) -> ( u +h w ) = ( w +h u ) ) |
15 |
14
|
3adant2 |
|- ( ( u e. ~H /\ v e. ~H /\ w e. ~H ) -> ( u +h w ) = ( w +h u ) ) |
16 |
15
|
eqeq1d |
|- ( ( u e. ~H /\ v e. ~H /\ w e. ~H ) -> ( ( u +h w ) = v <-> ( w +h u ) = v ) ) |
17 |
13 16
|
bitr4d |
|- ( ( u e. ~H /\ v e. ~H /\ w e. ~H ) -> ( ( v -h w ) = u <-> ( u +h w ) = v ) ) |
18 |
9 3 11 17
|
syl3an |
|- ( ( u e. B /\ v e. A /\ w e. ( _|_ ` B ) ) -> ( ( v -h w ) = u <-> ( u +h w ) = v ) ) |
19 |
|
eqcom |
|- ( u = ( v -h w ) <-> ( v -h w ) = u ) |
20 |
|
eqcom |
|- ( v = ( u +h w ) <-> ( u +h w ) = v ) |
21 |
18 19 20
|
3bitr4g |
|- ( ( u e. B /\ v e. A /\ w e. ( _|_ ` B ) ) -> ( u = ( v -h w ) <-> v = ( u +h w ) ) ) |
22 |
21
|
3expa |
|- ( ( ( u e. B /\ v e. A ) /\ w e. ( _|_ ` B ) ) -> ( u = ( v -h w ) <-> v = ( u +h w ) ) ) |
23 |
22
|
rexbidva |
|- ( ( u e. B /\ v e. A ) -> ( E. w e. ( _|_ ` B ) u = ( v -h w ) <-> E. w e. ( _|_ ` B ) v = ( u +h w ) ) ) |
24 |
8 23
|
bitr4d |
|- ( ( u e. B /\ v e. A ) -> ( ( ( projh ` B ) ` v ) = u <-> E. w e. ( _|_ ` B ) u = ( v -h w ) ) ) |
25 |
24
|
rexbidva |
|- ( u e. B -> ( E. v e. A ( ( projh ` B ) ` v ) = u <-> E. v e. A E. w e. ( _|_ ` B ) u = ( v -h w ) ) ) |
26 |
2
|
pjfni |
|- ( projh ` B ) Fn ~H |
27 |
1
|
shssii |
|- A C_ ~H |
28 |
|
fvelimab |
|- ( ( ( projh ` B ) Fn ~H /\ A C_ ~H ) -> ( u e. ( ( projh ` B ) " A ) <-> E. v e. A ( ( projh ` B ) ` v ) = u ) ) |
29 |
26 27 28
|
mp2an |
|- ( u e. ( ( projh ` B ) " A ) <-> E. v e. A ( ( projh ` B ) ` v ) = u ) |
30 |
10
|
chshii |
|- ( _|_ ` B ) e. SH |
31 |
|
shsel3 |
|- ( ( A e. SH /\ ( _|_ ` B ) e. SH ) -> ( u e. ( A +H ( _|_ ` B ) ) <-> E. v e. A E. w e. ( _|_ ` B ) u = ( v -h w ) ) ) |
32 |
1 30 31
|
mp2an |
|- ( u e. ( A +H ( _|_ ` B ) ) <-> E. v e. A E. w e. ( _|_ ` B ) u = ( v -h w ) ) |
33 |
25 29 32
|
3bitr4g |
|- ( u e. B -> ( u e. ( ( projh ` B ) " A ) <-> u e. ( A +H ( _|_ ` B ) ) ) ) |
34 |
33
|
pm5.32ri |
|- ( ( u e. ( ( projh ` B ) " A ) /\ u e. B ) <-> ( u e. ( A +H ( _|_ ` B ) ) /\ u e. B ) ) |
35 |
|
imassrn |
|- ( ( projh ` B ) " A ) C_ ran ( projh ` B ) |
36 |
2
|
pjrni |
|- ran ( projh ` B ) = B |
37 |
35 36
|
sseqtri |
|- ( ( projh ` B ) " A ) C_ B |
38 |
37
|
sseli |
|- ( u e. ( ( projh ` B ) " A ) -> u e. B ) |
39 |
38
|
pm4.71i |
|- ( u e. ( ( projh ` B ) " A ) <-> ( u e. ( ( projh ` B ) " A ) /\ u e. B ) ) |
40 |
|
elin |
|- ( u e. ( ( A +H ( _|_ ` B ) ) i^i B ) <-> ( u e. ( A +H ( _|_ ` B ) ) /\ u e. B ) ) |
41 |
34 39 40
|
3bitr4i |
|- ( u e. ( ( projh ` B ) " A ) <-> u e. ( ( A +H ( _|_ ` B ) ) i^i B ) ) |
42 |
41
|
eqriv |
|- ( ( projh ` B ) " A ) = ( ( A +H ( _|_ ` B ) ) i^i B ) |