Metamath Proof Explorer


Theorem f1imacnv

Description: Preimage of an image. (Contributed by NM, 30-Sep-2004)

Ref Expression
Assertion f1imacnv F : A 1-1 B C A F -1 F C = C

Proof

Step Hyp Ref Expression
1 resima F -1 F C F C = F -1 F C
2 df-f1 F : A 1-1 B F : A B Fun F -1
3 2 simprbi F : A 1-1 B Fun F -1
4 3 adantr F : A 1-1 B C A Fun F -1
5 funcnvres Fun F -1 F C -1 = F -1 F C
6 4 5 syl F : A 1-1 B C A F C -1 = F -1 F C
7 6 imaeq1d F : A 1-1 B C A F C -1 F C = F -1 F C F C
8 f1ores F : A 1-1 B C A F C : C 1-1 onto F C
9 f1ocnv F C : C 1-1 onto F C F C -1 : F C 1-1 onto C
10 8 9 syl F : A 1-1 B C A F C -1 : F C 1-1 onto C
11 imadmrn F C -1 dom F C -1 = ran F C -1
12 f1odm F C -1 : F C 1-1 onto C dom F C -1 = F C
13 12 imaeq2d F C -1 : F C 1-1 onto C F C -1 dom F C -1 = F C -1 F C
14 f1ofo F C -1 : F C 1-1 onto C F C -1 : F C onto C
15 forn F C -1 : F C onto C ran F C -1 = C
16 14 15 syl F C -1 : F C 1-1 onto C ran F C -1 = C
17 11 13 16 3eqtr3a F C -1 : F C 1-1 onto C F C -1 F C = C
18 10 17 syl F : A 1-1 B C A F C -1 F C = C
19 7 18 eqtr3d F : A 1-1 B C A F -1 F C F C = C
20 1 19 eqtr3id F : A 1-1 B C A F -1 F C = C