Description: Move conjunction outside of biconditional. (Contributed by Mario Carneiro, 11-Sep-2015)
Ref | Expression | ||
---|---|---|---|
Hypothesis | baibd.1 | |- ( ph -> ( ps <-> ( ch /\ th ) ) ) |
|
Assertion | rbaibd | |- ( ( ph /\ th ) -> ( ps <-> ch ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | baibd.1 | |- ( ph -> ( ps <-> ( ch /\ th ) ) ) |
|
2 | 1 | biancomd | |- ( ph -> ( ps <-> ( th /\ ch ) ) ) |
3 | 2 | baibd | |- ( ( ph /\ th ) -> ( ps <-> ch ) ) |