Description: Importation inference from a logical equivalence. (Contributed by NM, 3-May-1994)
Ref | Expression | ||
---|---|---|---|
Hypothesis | biimpa.1 | |- ( ph -> ( ps <-> ch ) ) |
|
Assertion | biimpar | |- ( ( ph /\ ch ) -> ps ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | biimpa.1 | |- ( ph -> ( ps <-> ch ) ) |
|
2 | 1 | biimprd | |- ( ph -> ( ch -> ps ) ) |
3 | 2 | imp | |- ( ( ph /\ ch ) -> ps ) |