Metamath Proof Explorer


Theorem fimacnvinrn

Description: Taking the converse image of a set can be limited to the range of the function used. (Contributed by Thierry Arnoux, 21-Jan-2017)

Ref Expression
Assertion fimacnvinrn Fun F F -1 A = F -1 A ran F

Proof

Step Hyp Ref Expression
1 inpreima Fun F F -1 A ran F = F -1 A F -1 ran F
2 funforn Fun F F : dom F onto ran F
3 fof F : dom F onto ran F F : dom F ran F
4 2 3 sylbi Fun F F : dom F ran F
5 fimacnv F : dom F ran F F -1 ran F = dom F
6 4 5 syl Fun F F -1 ran F = dom F
7 6 ineq2d Fun F F -1 A F -1 ran F = F -1 A dom F
8 cnvresima F dom F -1 A = F -1 A dom F
9 resdm2 F dom F = F -1 -1
10 funrel Fun F Rel F
11 dfrel2 Rel F F -1 -1 = F
12 10 11 sylib Fun F F -1 -1 = F
13 9 12 syl5eq Fun F F dom F = F
14 13 cnveqd Fun F F dom F -1 = F -1
15 14 imaeq1d Fun F F dom F -1 A = F -1 A
16 8 15 syl5eqr Fun F F -1 A dom F = F -1 A
17 1 7 16 3eqtrrd Fun F F -1 A = F -1 A ran F