Metamath Proof Explorer


Definition df-cj

Description: Define the complex conjugate function. See cjcli for its closure and cjval for its value. (Contributed by NM, 9-May-1999) (Revised by Mario Carneiro, 6-Nov-2013)

Ref Expression
Assertion df-cj
|- * = ( x e. CC |-> ( iota_ y e. CC ( ( x + y ) e. RR /\ ( _i x. ( x - y ) ) e. RR ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 ccj
 |-  *
1 vx
 |-  x
2 cc
 |-  CC
3 vy
 |-  y
4 1 cv
 |-  x
5 caddc
 |-  +
6 3 cv
 |-  y
7 4 6 5 co
 |-  ( x + y )
8 cr
 |-  RR
9 7 8 wcel
 |-  ( x + y ) e. RR
10 ci
 |-  _i
11 cmul
 |-  x.
12 cmin
 |-  -
13 4 6 12 co
 |-  ( x - y )
14 10 13 11 co
 |-  ( _i x. ( x - y ) )
15 14 8 wcel
 |-  ( _i x. ( x - y ) ) e. RR
16 9 15 wa
 |-  ( ( x + y ) e. RR /\ ( _i x. ( x - y ) ) e. RR )
17 16 3 2 crio
 |-  ( iota_ y e. CC ( ( x + y ) e. RR /\ ( _i x. ( x - y ) ) e. RR ) )
18 1 2 17 cmpt
 |-  ( x e. CC |-> ( iota_ y e. CC ( ( x + y ) e. RR /\ ( _i x. ( x - y ) ) e. RR ) ) )
19 0 18 wceq
 |-  * = ( x e. CC |-> ( iota_ y e. CC ( ( x + y ) e. RR /\ ( _i x. ( x - y ) ) e. RR ) ) )