Description: Prove isomorphic by an explicit isomorphism. (Contributed by Stefan O'Rear, 25-Jan-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | brgici | |- ( F e. ( R GrpIso S ) -> R ~=g S ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | ne0i | |- ( F e. ( R GrpIso S ) -> ( R GrpIso S ) =/= (/) ) | |
| 2 | brgic | |- ( R ~=g S <-> ( R GrpIso S ) =/= (/) ) | |
| 3 | 1 2 | sylibr | |- ( F e. ( R GrpIso S ) -> R ~=g S ) |