Description: The multiplicative monoid of a topological ring is a topological monoid. (Contributed by Mario Carneiro, 5-Oct-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | istrg.1 | |- M = ( mulGrp ` R ) |
|
| Assertion | trgtmd | |- ( R e. TopRing -> M e. TopMnd ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | istrg.1 | |- M = ( mulGrp ` R ) |
|
| 2 | 1 | istrg | |- ( R e. TopRing <-> ( R e. TopGrp /\ R e. Ring /\ M e. TopMnd ) ) |
| 3 | 2 | simp3bi | |- ( R e. TopRing -> M e. TopMnd ) |