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| Description: Define the domain of a class. Definition 3 of [Suppes] p. 59. |
| Ref | Expression |
|---|---|
| df-dm |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | cA |
. . 3
| |
| 2 | 1 | cdm 3251 |
. 2
|
| 3 | vx |
. . . . . 6
| |
| 4 | 3 | cv 991 |
. . . . 5
|
| 5 | vy |
. . . . . 6
| |
| 6 | 5 | cv 991 |
. . . . 5
|
| 7 | 4, 6, 1 | wbr 2692 |
. . . 4
|
| 8 | 7, 5 | wex 1016 |
. . 3
|
| 9 | 8, 3 | cab 1505 |
. 2
|
| 10 | 2, 9 | wceq 992 |
1
|
| Colors of variables: wff set class |
| This definition is referenced by: dfdm3 3393 dfrn2 3394 dfdm4 3396 eldm 3398 dmi 3415 dm0rn0 3417 dmcoss 3450 domleqt 10792 |