Metamath Proof Explorer


Definition df-ginv

Description: Define a function that maps a group operation to the group's inverse function. (Contributed by NM, 26-Oct-2006) (New usage is discouraged.)

Ref Expression
Assertion df-ginv
|- inv = ( g e. GrpOp |-> ( x e. ran g |-> ( iota_ z e. ran g ( z g x ) = ( GId ` g ) ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cgn
 |-  inv
1 vg
 |-  g
2 cgr
 |-  GrpOp
3 vx
 |-  x
4 1 cv
 |-  g
5 4 crn
 |-  ran g
6 vz
 |-  z
7 6 cv
 |-  z
8 3 cv
 |-  x
9 7 8 4 co
 |-  ( z g x )
10 cgi
 |-  GId
11 4 10 cfv
 |-  ( GId ` g )
12 9 11 wceq
 |-  ( z g x ) = ( GId ` g )
13 12 6 5 crio
 |-  ( iota_ z e. ran g ( z g x ) = ( GId ` g ) )
14 3 5 13 cmpt
 |-  ( x e. ran g |-> ( iota_ z e. ran g ( z g x ) = ( GId ` g ) ) )
15 1 2 14 cmpt
 |-  ( g e. GrpOp |-> ( x e. ran g |-> ( iota_ z e. ran g ( z g x ) = ( GId ` g ) ) ) )
16 0 15 wceq
 |-  inv = ( g e. GrpOp |-> ( x e. ran g |-> ( iota_ z e. ran g ( z g x ) = ( GId ` g ) ) ) )