Description: Alternate proof of 3jcad . (Contributed by Hongxiu Chen, 29-Jun-2025) (Proof modification is discouraged.) Use 3jcad instead. (New usage is discouraged.)
Ref | Expression | ||
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Hypotheses | 3jcadALT.1 | |- ( ph -> ( ps -> ch ) ) |
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3jcadALT.2 | |- ( ph -> ( ps -> th ) ) |
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3jcadALT.3 | |- ( ph -> ( ps -> ta ) ) |
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Assertion | 3jcadALT | |- ( ph -> ( ps -> ( ch /\ th /\ ta ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 3jcadALT.1 | |- ( ph -> ( ps -> ch ) ) |
|
2 | 3jcadALT.2 | |- ( ph -> ( ps -> th ) ) |
|
3 | 3jcadALT.3 | |- ( ph -> ( ps -> ta ) ) |
|
4 | 1 2 | jcad | |- ( ph -> ( ps -> ( ch /\ th ) ) ) |
5 | 4 3 | jcad | |- ( ph -> ( ps -> ( ( ch /\ th ) /\ ta ) ) ) |
6 | df-3an | |- ( ( ch /\ th /\ ta ) <-> ( ( ch /\ th ) /\ ta ) ) |
|
7 | 5 6 | imbitrrdi | |- ( ph -> ( ps -> ( ch /\ th /\ ta ) ) ) |