Description: Membership in a class abstraction, using implicit substitution. (Contributed by NM, 13-Sep-1995)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | elab2g.1 | |- ( x = A -> ( ph <-> ps ) ) |
|
| elab2g.2 | |- B = { x | ph } |
||
| Assertion | elab2g | |- ( A e. V -> ( A e. B <-> ps ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elab2g.1 | |- ( x = A -> ( ph <-> ps ) ) |
|
| 2 | elab2g.2 | |- B = { x | ph } |
|
| 3 | 2 | eleq2i | |- ( A e. B <-> A e. { x | ph } ) |
| 4 | 1 | elabg | |- ( A e. V -> ( A e. { x | ph } <-> ps ) ) |
| 5 | 3 4 | bitrid | |- ( A e. V -> ( A e. B <-> ps ) ) |