Description: Add true as a conjunct. (Contributed by Giovanni Mascellani, 23-May-2019)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | truconj | |- ( ph <-> ( T. /\ ph ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | truan | |- ( ( T. /\ ph ) <-> ph ) |
|
| 2 | 1 | bicomi | |- ( ph <-> ( T. /\ ph ) ) |