Description: Deduction form of bound-variable hypothesis builder nf3an . (Contributed by NM, 17-Feb-2013) (Revised by Mario Carneiro, 16-Oct-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | nfand.1 | |- ( ph -> F/ x ps ) |
|
| nfand.2 | |- ( ph -> F/ x ch ) |
||
| nfand.3 | |- ( ph -> F/ x th ) |
||
| Assertion | nf3and | |- ( ph -> F/ x ( ps /\ ch /\ th ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | nfand.1 | |- ( ph -> F/ x ps ) |
|
| 2 | nfand.2 | |- ( ph -> F/ x ch ) |
|
| 3 | nfand.3 | |- ( ph -> F/ x th ) |
|
| 4 | df-3an | |- ( ( ps /\ ch /\ th ) <-> ( ( ps /\ ch ) /\ th ) ) |
|
| 5 | 1 2 | nfand | |- ( ph -> F/ x ( ps /\ ch ) ) |
| 6 | 5 3 | nfand | |- ( ph -> F/ x ( ( ps /\ ch ) /\ th ) ) |
| 7 | 4 6 | nfxfrd | |- ( ph -> F/ x ( ps /\ ch /\ th ) ) |