| Step |
Hyp |
Ref |
Expression |
| 1 |
|
lcvfbr.s |
|- S = ( LSubSp ` W ) |
| 2 |
|
lcvfbr.c |
|- C = (
|
| 3 |
|
lcvfbr.w |
|- ( ph -> W e. X ) |
| 4 |
|
lcvfbr.t |
|- ( ph -> T e. S ) |
| 5 |
|
lcvfbr.u |
|- ( ph -> U e. S ) |
| 6 |
1 2 3 4 5
|
lcvbr |
|- ( ph -> ( T C U <-> ( T C. U /\ -. E. s e. S ( T C. s /\ s C. U ) ) ) ) |
| 7 |
|
iman |
|- ( ( ( T C_ s /\ s C_ U ) -> ( s = T \/ s = U ) ) <-> -. ( ( T C_ s /\ s C_ U ) /\ -. ( s = T \/ s = U ) ) ) |
| 8 |
|
df-pss |
|- ( T C. s <-> ( T C_ s /\ T =/= s ) ) |
| 9 |
|
necom |
|- ( T =/= s <-> s =/= T ) |
| 10 |
9
|
anbi2i |
|- ( ( T C_ s /\ T =/= s ) <-> ( T C_ s /\ s =/= T ) ) |
| 11 |
8 10
|
bitri |
|- ( T C. s <-> ( T C_ s /\ s =/= T ) ) |
| 12 |
|
df-pss |
|- ( s C. U <-> ( s C_ U /\ s =/= U ) ) |
| 13 |
11 12
|
anbi12i |
|- ( ( T C. s /\ s C. U ) <-> ( ( T C_ s /\ s =/= T ) /\ ( s C_ U /\ s =/= U ) ) ) |
| 14 |
|
an4 |
|- ( ( ( T C_ s /\ s =/= T ) /\ ( s C_ U /\ s =/= U ) ) <-> ( ( T C_ s /\ s C_ U ) /\ ( s =/= T /\ s =/= U ) ) ) |
| 15 |
|
neanior |
|- ( ( s =/= T /\ s =/= U ) <-> -. ( s = T \/ s = U ) ) |
| 16 |
15
|
anbi2i |
|- ( ( ( T C_ s /\ s C_ U ) /\ ( s =/= T /\ s =/= U ) ) <-> ( ( T C_ s /\ s C_ U ) /\ -. ( s = T \/ s = U ) ) ) |
| 17 |
14 16
|
bitri |
|- ( ( ( T C_ s /\ s =/= T ) /\ ( s C_ U /\ s =/= U ) ) <-> ( ( T C_ s /\ s C_ U ) /\ -. ( s = T \/ s = U ) ) ) |
| 18 |
13 17
|
bitri |
|- ( ( T C. s /\ s C. U ) <-> ( ( T C_ s /\ s C_ U ) /\ -. ( s = T \/ s = U ) ) ) |
| 19 |
7 18
|
xchbinxr |
|- ( ( ( T C_ s /\ s C_ U ) -> ( s = T \/ s = U ) ) <-> -. ( T C. s /\ s C. U ) ) |
| 20 |
19
|
ralbii |
|- ( A. s e. S ( ( T C_ s /\ s C_ U ) -> ( s = T \/ s = U ) ) <-> A. s e. S -. ( T C. s /\ s C. U ) ) |
| 21 |
|
ralnex |
|- ( A. s e. S -. ( T C. s /\ s C. U ) <-> -. E. s e. S ( T C. s /\ s C. U ) ) |
| 22 |
20 21
|
bitri |
|- ( A. s e. S ( ( T C_ s /\ s C_ U ) -> ( s = T \/ s = U ) ) <-> -. E. s e. S ( T C. s /\ s C. U ) ) |
| 23 |
22
|
anbi2i |
|- ( ( T C. U /\ A. s e. S ( ( T C_ s /\ s C_ U ) -> ( s = T \/ s = U ) ) ) <-> ( T C. U /\ -. E. s e. S ( T C. s /\ s C. U ) ) ) |
| 24 |
6 23
|
bitr4di |
|- ( ph -> ( T C U <-> ( T C. U /\ A. s e. S ( ( T C_ s /\ s C_ U ) -> ( s = T \/ s = U ) ) ) ) ) |