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| Mirrors > Home > NFE Home > Th. List > df-image | Unicode version | ||
| Description: Define the image function of a class. (Contributed by SF, 9-Feb-2015.) (Revised by Scott Fenton, 19-Apr-2021.) | 
| Ref | Expression | 
|---|---|
| df-image | 
 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | cA | 
. . 3
 | |
| 2 | 1 | cimage 5754 | 
. 2
 | 
| 3 | csset 4720 | 
. . . . . 6
 | |
| 4 | 3 | cins2 5750 | 
. . . . 5
 | 
| 5 | 1 | csi 4721 | 
. . . . . . . 8
 | 
| 6 | 5 | ccnv 4772 | 
. . . . . . 7
 | 
| 7 | 3, 6 | ccom 4722 | 
. . . . . 6
 | 
| 8 | 7 | cins3 5752 | 
. . . . 5
 | 
| 9 | 4, 8 | csymdif 3210 | 
. . . 4
 | 
| 10 | c1c 4135 | 
. . . 4
 | |
| 11 | 9, 10 | cima 4723 | 
. . 3
 | 
| 12 | 11 | ccompl 3206 | 
. 2
 | 
| 13 | 2, 12 | wceq 1642 | 
1
 | 
| Colors of variables: wff setvar class | 
| This definition is referenced by: brimage 5794 imageexg 5801 | 
| Copyright terms: Public domain | W3C validator |