Description: Equivalence with a conjunction one of whose conjuncts is a consequence of the other. Deduction form. (Contributed by Zhi Wang, 24-Sep-2024)
Ref | Expression | ||
---|---|---|---|
Hypotheses | mpbiran3d.1 | |- ( ph -> ( ps <-> ( ch /\ th ) ) ) |
|
mpbiran3d.2 | |- ( ( ph /\ ch ) -> th ) |
||
Assertion | mpbiran3d | |- ( ph -> ( ps <-> ch ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | mpbiran3d.1 | |- ( ph -> ( ps <-> ( ch /\ th ) ) ) |
|
2 | mpbiran3d.2 | |- ( ( ph /\ ch ) -> th ) |
|
3 | 1 | simprbda | |- ( ( ph /\ ps ) -> ch ) |
4 | 3 | ex | |- ( ph -> ( ps -> ch ) ) |
5 | 2 | ex | |- ( ph -> ( ch -> th ) ) |
6 | 5 | ancld | |- ( ph -> ( ch -> ( ch /\ th ) ) ) |
7 | 6 1 | sylibrd | |- ( ph -> ( ch -> ps ) ) |
8 | 4 7 | impbid | |- ( ph -> ( ps <-> ch ) ) |