| Step |
Hyp |
Ref |
Expression |
| 1 |
|
df-nan |
|- ( ( ph -/\ ps ) <-> -. ( ph /\ ps ) ) |
| 2 |
|
xor2 |
|- ( ( ph \/_ ps ) <-> ( ( ph \/ ps ) /\ -. ( ph /\ ps ) ) ) |
| 3 |
2
|
rbaibr |
|- ( -. ( ph /\ ps ) -> ( ( ph \/ ps ) <-> ( ph \/_ ps ) ) ) |
| 4 |
2
|
bibi2i |
|- ( ( ( ph \/ ps ) <-> ( ph \/_ ps ) ) <-> ( ( ph \/ ps ) <-> ( ( ph \/ ps ) /\ -. ( ph /\ ps ) ) ) ) |
| 5 |
|
pm4.71 |
|- ( ( ( ph \/ ps ) -> -. ( ph /\ ps ) ) <-> ( ( ph \/ ps ) <-> ( ( ph \/ ps ) /\ -. ( ph /\ ps ) ) ) ) |
| 6 |
|
simpl |
|- ( ( ph /\ ps ) -> ph ) |
| 7 |
6
|
orcd |
|- ( ( ph /\ ps ) -> ( ph \/ ps ) ) |
| 8 |
7
|
con3i |
|- ( -. ( ph \/ ps ) -> -. ( ph /\ ps ) ) |
| 9 |
|
id |
|- ( -. ( ph /\ ps ) -> -. ( ph /\ ps ) ) |
| 10 |
8 9
|
ja |
|- ( ( ( ph \/ ps ) -> -. ( ph /\ ps ) ) -> -. ( ph /\ ps ) ) |
| 11 |
5 10
|
sylbir |
|- ( ( ( ph \/ ps ) <-> ( ( ph \/ ps ) /\ -. ( ph /\ ps ) ) ) -> -. ( ph /\ ps ) ) |
| 12 |
4 11
|
sylbi |
|- ( ( ( ph \/ ps ) <-> ( ph \/_ ps ) ) -> -. ( ph /\ ps ) ) |
| 13 |
3 12
|
impbii |
|- ( -. ( ph /\ ps ) <-> ( ( ph \/ ps ) <-> ( ph \/_ ps ) ) ) |
| 14 |
1 13
|
bitri |
|- ( ( ph -/\ ps ) <-> ( ( ph \/ ps ) <-> ( ph \/_ ps ) ) ) |