| Step |
Hyp |
Ref |
Expression |
| 1 |
|
h0elch |
|- 0H e. CH |
| 2 |
1
|
choccli |
|- ( _|_ ` 0H ) e. CH |
| 3 |
|
chjcl |
|- ( ( ( _|_ ` 0H ) e. CH /\ A e. CH ) -> ( ( _|_ ` 0H ) vH A ) e. CH ) |
| 4 |
2 3
|
mpan |
|- ( A e. CH -> ( ( _|_ ` 0H ) vH A ) e. CH ) |
| 5 |
|
chm0 |
|- ( ( ( _|_ ` 0H ) vH A ) e. CH -> ( ( ( _|_ ` 0H ) vH A ) i^i 0H ) = 0H ) |
| 6 |
4 5
|
syl |
|- ( A e. CH -> ( ( ( _|_ ` 0H ) vH A ) i^i 0H ) = 0H ) |
| 7 |
|
chm0 |
|- ( A e. CH -> ( A i^i 0H ) = 0H ) |
| 8 |
6 7
|
eqtr4d |
|- ( A e. CH -> ( ( ( _|_ ` 0H ) vH A ) i^i 0H ) = ( A i^i 0H ) ) |
| 9 |
|
incom |
|- ( 0H i^i ( ( _|_ ` 0H ) vH A ) ) = ( ( ( _|_ ` 0H ) vH A ) i^i 0H ) |
| 10 |
|
incom |
|- ( 0H i^i A ) = ( A i^i 0H ) |
| 11 |
8 9 10
|
3eqtr4g |
|- ( A e. CH -> ( 0H i^i ( ( _|_ ` 0H ) vH A ) ) = ( 0H i^i A ) ) |
| 12 |
|
cmbr3 |
|- ( ( 0H e. CH /\ A e. CH ) -> ( 0H C_H A <-> ( 0H i^i ( ( _|_ ` 0H ) vH A ) ) = ( 0H i^i A ) ) ) |
| 13 |
1 12
|
mpan |
|- ( A e. CH -> ( 0H C_H A <-> ( 0H i^i ( ( _|_ ` 0H ) vH A ) ) = ( 0H i^i A ) ) ) |
| 14 |
11 13
|
mpbird |
|- ( A e. CH -> 0H C_H A ) |