Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | bnj1517.1 | |- A = { x | ( ph /\ ps ) } | |
| Assertion | bnj1517 | |- ( x e. A -> ps ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | bnj1517.1 |  |-  A = { x | ( ph /\ ps ) } | |
| 2 | 1 | bnj1436 | |- ( x e. A -> ( ph /\ ps ) ) | 
| 3 | 2 | simprd | |- ( x e. A -> ps ) |