Description: Membership in a class abstraction, using implicit substitution. Deduction version of elab . (Contributed by GG, 12-Oct-2024)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | elabd3.ex | |- ( ph -> A e. V ) |
|
| elabd3.is | |- ( ( ph /\ x = A ) -> ( ps <-> ch ) ) |
||
| Assertion | elabd3 | |- ( ph -> ( A e. { x | ps } <-> ch ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elabd3.ex | |- ( ph -> A e. V ) |
|
| 2 | elabd3.is | |- ( ( ph /\ x = A ) -> ( ps <-> ch ) ) |
|
| 3 | eqidd | |- ( ph -> { x | ps } = { x | ps } ) |
|
| 4 | 1 3 2 | elabd2 | |- ( ph -> ( A e. { x | ps } <-> ch ) ) |