Description: An element of the powerset of B intersected with anything, is a subset of B . (Contributed by Glauco Siliprandi, 17-Aug-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | elpwinss | |- ( A e. ( ~P B i^i C ) -> A C_ B ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elinel1 | |- ( A e. ( ~P B i^i C ) -> A e. ~P B ) |
|
| 2 | 1 | elpwid | |- ( A e. ( ~P B i^i C ) -> A C_ B ) |