Description: The range of the quotient map is the quotient carrier. It lets us replace quotient-carrier reasoning by map/range reasoning (and conversely) via df-qmap and dfqs2 . (Contributed by Peter Mazsa, 12-Feb-2026)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rnqmap | |- ran QMap R = ( dom R /. R ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-qmap | |- QMap R = ( x e. dom R |-> [ x ] R ) |
|
| 2 | 1 | rneqi | |- ran QMap R = ran ( x e. dom R |-> [ x ] R ) |
| 3 | dfqs2 | |- ( dom R /. R ) = ran ( x e. dom R |-> [ x ] R ) |
|
| 4 | 2 3 | eqtr4i | |- ran QMap R = ( dom R /. R ) |