Description: A rearrangement of conjuncts. (Contributed by NM, 12-Mar-1995) (Proof shortened by Wolf Lammen, 25-Dec-2012)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | an32 | |- ( ( ( ph /\ ps ) /\ ch ) <-> ( ( ph /\ ch ) /\ ps ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | an21 | |- ( ( ( ph /\ ps ) /\ ch ) <-> ( ps /\ ( ph /\ ch ) ) ) |
|
| 2 | 1 | biancomi | |- ( ( ( ph /\ ps ) /\ ch ) <-> ( ( ph /\ ch ) /\ ps ) ) |