Description: Define class of all division rings. A division ring is a ring in which the set of units is exactly the nonzero elements of the ring. (Contributed by NM, 18-Oct-2012)
Ref | Expression | ||
---|---|---|---|
Assertion | df-drng | |- DivRing = { r e. Ring | ( Unit ` r ) = ( ( Base ` r ) \ { ( 0g ` r ) } ) } |
Step | Hyp | Ref | Expression |
---|---|---|---|
0 | cdr | |- DivRing |
|
1 | vr | |- r |
|
2 | crg | |- Ring |
|
3 | cui | |- Unit |
|
4 | 1 | cv | |- r |
5 | 4 3 | cfv | |- ( Unit ` r ) |
6 | cbs | |- Base |
|
7 | 4 6 | cfv | |- ( Base ` r ) |
8 | c0g | |- 0g |
|
9 | 4 8 | cfv | |- ( 0g ` r ) |
10 | 9 | csn | |- { ( 0g ` r ) } |
11 | 7 10 | cdif | |- ( ( Base ` r ) \ { ( 0g ` r ) } ) |
12 | 5 11 | wceq | |- ( Unit ` r ) = ( ( Base ` r ) \ { ( 0g ` r ) } ) |
13 | 12 1 2 | crab | |- { r e. Ring | ( Unit ` r ) = ( ( Base ` r ) \ { ( 0g ` r ) } ) } |
14 | 0 13 | wceq | |- DivRing = { r e. Ring | ( Unit ` r ) = ( ( Base ` r ) \ { ( 0g ` r ) } ) } |