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Related theorems Unicode version |
| Description: If a class is a member of another class, it is a set. |
| Ref | Expression |
|---|---|
| elisseti.1 |
|
| Ref | Expression |
|---|---|
| elisseti |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elisseti.1 |
. 2
| |
| 2 | elisset 1813 |
. 2
| |
| 3 | 1, 2 | ax-mp 7 |
1
|