Metamath Proof Explorer


Theorem maprnin

Description: Restricting the range of the mapping operator. (Contributed by Thierry Arnoux, 30-Aug-2017)

Ref Expression
Hypotheses maprnin.1 AV
maprnin.2 BV
Assertion maprnin BCA=fBA|ranfC

Proof

Step Hyp Ref Expression
1 maprnin.1 AV
2 maprnin.2 BV
3 ffn f:ABfFnA
4 df-f f:ACfFnAranfC
5 4 baibr fFnAranfCf:AC
6 3 5 syl f:ABranfCf:AC
7 6 pm5.32i f:ABranfCf:ABf:AC
8 2 1 elmap fBAf:AB
9 8 anbi1i fBAranfCf:ABranfC
10 fin f:ABCf:ABf:AC
11 7 9 10 3bitr4ri f:ABCfBAranfC
12 11 abbii f|f:ABC=f|fBAranfC
13 2 inex1 BCV
14 13 1 mapval BCA=f|f:ABC
15 df-rab fBA|ranfC=f|fBAranfC
16 12 14 15 3eqtr4i BCA=fBA|ranfC