| Step |
Hyp |
Ref |
Expression |
| 1 |
|
simp2 |
|- ( ( A. x ( x = A -> B = C ) /\ F = ( x e. D |-> B ) /\ ( A e. D /\ C e. V ) ) -> F = ( x e. D |-> B ) ) |
| 2 |
1
|
fveq1d |
|- ( ( A. x ( x = A -> B = C ) /\ F = ( x e. D |-> B ) /\ ( A e. D /\ C e. V ) ) -> ( F ` A ) = ( ( x e. D |-> B ) ` A ) ) |
| 3 |
|
risset |
|- ( A e. D <-> E. x e. D x = A ) |
| 4 |
|
elex |
|- ( C e. V -> C e. _V ) |
| 5 |
|
nfa1 |
|- F/ x A. x ( x = A -> B = C ) |
| 6 |
|
nfv |
|- F/ x C e. _V |
| 7 |
|
nffvmpt1 |
|- F/_ x ( ( x e. D |-> B ) ` A ) |
| 8 |
7
|
nfeq1 |
|- F/ x ( ( x e. D |-> B ) ` A ) = C |
| 9 |
6 8
|
nfim |
|- F/ x ( C e. _V -> ( ( x e. D |-> B ) ` A ) = C ) |
| 10 |
|
simprl |
|- ( ( ( x = A /\ B = C ) /\ ( x e. D /\ C e. _V ) ) -> x e. D ) |
| 11 |
|
simplr |
|- ( ( ( x = A /\ B = C ) /\ ( x e. D /\ C e. _V ) ) -> B = C ) |
| 12 |
|
simprr |
|- ( ( ( x = A /\ B = C ) /\ ( x e. D /\ C e. _V ) ) -> C e. _V ) |
| 13 |
11 12
|
eqeltrd |
|- ( ( ( x = A /\ B = C ) /\ ( x e. D /\ C e. _V ) ) -> B e. _V ) |
| 14 |
|
eqid |
|- ( x e. D |-> B ) = ( x e. D |-> B ) |
| 15 |
14
|
fvmpt2 |
|- ( ( x e. D /\ B e. _V ) -> ( ( x e. D |-> B ) ` x ) = B ) |
| 16 |
10 13 15
|
syl2anc |
|- ( ( ( x = A /\ B = C ) /\ ( x e. D /\ C e. _V ) ) -> ( ( x e. D |-> B ) ` x ) = B ) |
| 17 |
|
simpll |
|- ( ( ( x = A /\ B = C ) /\ ( x e. D /\ C e. _V ) ) -> x = A ) |
| 18 |
17
|
fveq2d |
|- ( ( ( x = A /\ B = C ) /\ ( x e. D /\ C e. _V ) ) -> ( ( x e. D |-> B ) ` x ) = ( ( x e. D |-> B ) ` A ) ) |
| 19 |
16 18 11
|
3eqtr3d |
|- ( ( ( x = A /\ B = C ) /\ ( x e. D /\ C e. _V ) ) -> ( ( x e. D |-> B ) ` A ) = C ) |
| 20 |
19
|
exp43 |
|- ( x = A -> ( B = C -> ( x e. D -> ( C e. _V -> ( ( x e. D |-> B ) ` A ) = C ) ) ) ) |
| 21 |
20
|
a2i |
|- ( ( x = A -> B = C ) -> ( x = A -> ( x e. D -> ( C e. _V -> ( ( x e. D |-> B ) ` A ) = C ) ) ) ) |
| 22 |
21
|
com23 |
|- ( ( x = A -> B = C ) -> ( x e. D -> ( x = A -> ( C e. _V -> ( ( x e. D |-> B ) ` A ) = C ) ) ) ) |
| 23 |
22
|
sps |
|- ( A. x ( x = A -> B = C ) -> ( x e. D -> ( x = A -> ( C e. _V -> ( ( x e. D |-> B ) ` A ) = C ) ) ) ) |
| 24 |
5 9 23
|
rexlimd |
|- ( A. x ( x = A -> B = C ) -> ( E. x e. D x = A -> ( C e. _V -> ( ( x e. D |-> B ) ` A ) = C ) ) ) |
| 25 |
4 24
|
syl7 |
|- ( A. x ( x = A -> B = C ) -> ( E. x e. D x = A -> ( C e. V -> ( ( x e. D |-> B ) ` A ) = C ) ) ) |
| 26 |
3 25
|
biimtrid |
|- ( A. x ( x = A -> B = C ) -> ( A e. D -> ( C e. V -> ( ( x e. D |-> B ) ` A ) = C ) ) ) |
| 27 |
26
|
imp32 |
|- ( ( A. x ( x = A -> B = C ) /\ ( A e. D /\ C e. V ) ) -> ( ( x e. D |-> B ) ` A ) = C ) |
| 28 |
27
|
3adant2 |
|- ( ( A. x ( x = A -> B = C ) /\ F = ( x e. D |-> B ) /\ ( A e. D /\ C e. V ) ) -> ( ( x e. D |-> B ) ` A ) = C ) |
| 29 |
2 28
|
eqtrd |
|- ( ( A. x ( x = A -> B = C ) /\ F = ( x e. D |-> B ) /\ ( A e. D /\ C e. V ) ) -> ( F ` A ) = C ) |