Description: Inference commuting conjunction in antecedent. (Contributed by NM, 21-Apr-1994)
Ref | Expression | ||
---|---|---|---|
Hypothesis | ancoms.1 | |
|
Assertion | ancoms | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ancoms.1 | |
|
2 | 1 | expcom | |
3 | 2 | imp | |