| Step |
Hyp |
Ref |
Expression |
| 1 |
|
nelrnmpt.x |
|- F/ x ph |
| 2 |
|
nelrnmpt.f |
|- F = ( x e. A |-> B ) |
| 3 |
|
nelrnmpt.c |
|- ( ph -> C e. V ) |
| 4 |
|
nelrnmpt.n |
|- ( ( ph /\ x e. A ) -> C =/= B ) |
| 5 |
4
|
neneqd |
|- ( ( ph /\ x e. A ) -> -. C = B ) |
| 6 |
5
|
ex |
|- ( ph -> ( x e. A -> -. C = B ) ) |
| 7 |
1 6
|
ralrimi |
|- ( ph -> A. x e. A -. C = B ) |
| 8 |
|
ralnex |
|- ( A. x e. A -. C = B <-> -. E. x e. A C = B ) |
| 9 |
7 8
|
sylib |
|- ( ph -> -. E. x e. A C = B ) |
| 10 |
2
|
elrnmpt |
|- ( C e. V -> ( C e. ran F <-> E. x e. A C = B ) ) |
| 11 |
3 10
|
syl |
|- ( ph -> ( C e. ran F <-> E. x e. A C = B ) ) |
| 12 |
9 11
|
mtbird |
|- ( ph -> -. C e. ran F ) |