Description: A double syllogism inference. For an implication-only version, see syl2imc . (Contributed by NM, 17-Sep-2013)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | syl2an.1 | |- ( ph -> ps ) |
|
| syl2an.2 | |- ( ta -> ch ) |
||
| syl2an.3 | |- ( ( ps /\ ch ) -> th ) |
||
| Assertion | syl2anr | |- ( ( ta /\ ph ) -> th ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | syl2an.1 | |- ( ph -> ps ) |
|
| 2 | syl2an.2 | |- ( ta -> ch ) |
|
| 3 | syl2an.3 | |- ( ( ps /\ ch ) -> th ) |
|
| 4 | 1 2 3 | syl2an | |- ( ( ph /\ ta ) -> th ) |
| 5 | 4 | ancoms | |- ( ( ta /\ ph ) -> th ) |