Description: Dropping the base information off a sigma-algebra. (Contributed by Thierry Arnoux, 13-Feb-2017)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | elrnsiga | |- ( S e. ( sigAlgebra ` O ) -> S e. U. ran sigAlgebra ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | fvssunirn | |- ( sigAlgebra ` O ) C_ U. ran sigAlgebra |
|
| 2 | 1 | sseli | |- ( S e. ( sigAlgebra ` O ) -> S e. U. ran sigAlgebra ) |