Description: Detach a conjunction of truths in a biconditional. (Contributed by NM, 6-Nov-2011) (Proof shortened by Wolf Lammen, 24-Nov-2012)
Ref | Expression | ||
---|---|---|---|
Hypotheses | mpbi2and.1 | |- ( ph -> ps ) |
|
mpbi2and.2 | |- ( ph -> ch ) |
||
mpbi2and.3 | |- ( ph -> ( ( ps /\ ch ) <-> th ) ) |
||
Assertion | mpbi2and | |- ( ph -> th ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | mpbi2and.1 | |- ( ph -> ps ) |
|
2 | mpbi2and.2 | |- ( ph -> ch ) |
|
3 | mpbi2and.3 | |- ( ph -> ( ( ps /\ ch ) <-> th ) ) |
|
4 | 1 2 | jca | |- ( ph -> ( ps /\ ch ) ) |
5 | 4 3 | mpbid | |- ( ph -> th ) |