Description: Adding biconditional when antecedents are conjuncted. (Contributed by metakunt, 16-Apr-2024) (Proof shortened by Wolf Lammen, 7-May-2025)
Ref | Expression | ||
---|---|---|---|
Hypotheses | anbiim.1 | |- ( ph -> ( ch -> th ) ) |
|
anbiim.2 | |- ( ps -> ( th -> ch ) ) |
||
Assertion | anbiim | |- ( ( ph /\ ps ) -> ( ch <-> th ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | anbiim.1 | |- ( ph -> ( ch -> th ) ) |
|
2 | anbiim.2 | |- ( ps -> ( th -> ch ) ) |
|
3 | 1 | adantr | |- ( ( ph /\ ps ) -> ( ch -> th ) ) |
4 | 2 | adantl | |- ( ( ph /\ ps ) -> ( th -> ch ) ) |
5 | 3 4 | impbid | |- ( ( ph /\ ps ) -> ( ch <-> th ) ) |