Metamath Proof Explorer


Definition df-invr

Description: Define multiplicative inverse. (Contributed by NM, 21-Sep-2011)

Ref Expression
Assertion df-invr
|- invr = ( r e. _V |-> ( invg ` ( ( mulGrp ` r ) |`s ( Unit ` r ) ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cinvr
 |-  invr
1 vr
 |-  r
2 cvv
 |-  _V
3 cminusg
 |-  invg
4 cmgp
 |-  mulGrp
5 1 cv
 |-  r
6 5 4 cfv
 |-  ( mulGrp ` r )
7 cress
 |-  |`s
8 cui
 |-  Unit
9 5 8 cfv
 |-  ( Unit ` r )
10 6 9 7 co
 |-  ( ( mulGrp ` r ) |`s ( Unit ` r ) )
11 10 3 cfv
 |-  ( invg ` ( ( mulGrp ` r ) |`s ( Unit ` r ) ) )
12 1 2 11 cmpt
 |-  ( r e. _V |-> ( invg ` ( ( mulGrp ` r ) |`s ( Unit ` r ) ) ) )
13 0 12 wceq
 |-  invr = ( r e. _V |-> ( invg ` ( ( mulGrp ` r ) |`s ( Unit ` r ) ) ) )