Description: Deduction adding a conjunct to antecedent. (Contributed by NM, 4-May-1994) (Proof shortened by Wolf Lammen, 24-Nov-2012)
Ref | Expression | ||
---|---|---|---|
Hypothesis | adant2.1 | |- ( ( ph /\ ps ) -> ch ) |
|
Assertion | adantll | |- ( ( ( th /\ ph ) /\ ps ) -> ch ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | adant2.1 | |- ( ( ph /\ ps ) -> ch ) |
|
2 | simpr | |- ( ( th /\ ph ) -> ph ) |
|
3 | 2 1 | sylan | |- ( ( ( th /\ ph ) /\ ps ) -> ch ) |