| Step |
Hyp |
Ref |
Expression |
| 1 |
|
an62ds.1 |
|- ( ( ( ( ( ( ph /\ ps ) /\ ch ) /\ th ) /\ ta ) /\ et ) -> ze ) |
| 2 |
|
an32 |
|- ( ( ( ph /\ ps ) /\ et ) <-> ( ( ph /\ et ) /\ ps ) ) |
| 3 |
2
|
anbi1i |
|- ( ( ( ( ph /\ ps ) /\ et ) /\ th ) <-> ( ( ( ph /\ et ) /\ ps ) /\ th ) ) |
| 4 |
3
|
anbi1i |
|- ( ( ( ( ( ph /\ ps ) /\ et ) /\ th ) /\ ta ) <-> ( ( ( ( ph /\ et ) /\ ps ) /\ th ) /\ ta ) ) |
| 5 |
1
|
an52ds |
|- ( ( ( ( ( ( ph /\ ps ) /\ et ) /\ th ) /\ ta ) /\ ch ) -> ze ) |
| 6 |
4 5
|
sylanbr |
|- ( ( ( ( ( ( ph /\ et ) /\ ps ) /\ th ) /\ ta ) /\ ch ) -> ze ) |
| 7 |
6
|
an52ds |
|- ( ( ( ( ( ( ph /\ et ) /\ ch ) /\ th ) /\ ta ) /\ ps ) -> ze ) |