Description: Conjoin antecedents and consequents of two premises. (Contributed by NM, 3-Jan-1993) (Proof shortened by Wolf Lammen, 14-Dec-2013)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | anim12i.1 | |- ( ph -> ps ) |
|
| anim12i.2 | |- ( ch -> th ) |
||
| Assertion | anim12i | |- ( ( ph /\ ch ) -> ( ps /\ th ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | anim12i.1 | |- ( ph -> ps ) |
|
| 2 | anim12i.2 | |- ( ch -> th ) |
|
| 3 | id | |- ( ( ps /\ th ) -> ( ps /\ th ) ) |
|
| 4 | 1 2 3 | syl2an | |- ( ( ph /\ ch ) -> ( ps /\ th ) ) |