Step |
Hyp |
Ref |
Expression |
1 |
|
elex |
|- ( W e. V -> W e. _V ) |
2 |
|
fveq2 |
|- ( w = W -> ( # ` w ) = ( # ` W ) ) |
3 |
2
|
oveq2d |
|- ( w = W -> ( 0 ..^ ( # ` w ) ) = ( 0 ..^ ( # ` W ) ) ) |
4 |
|
id |
|- ( w = W -> w = W ) |
5 |
2
|
oveq1d |
|- ( w = W -> ( ( # ` w ) - 1 ) = ( ( # ` W ) - 1 ) ) |
6 |
5
|
oveq1d |
|- ( w = W -> ( ( ( # ` w ) - 1 ) - x ) = ( ( ( # ` W ) - 1 ) - x ) ) |
7 |
4 6
|
fveq12d |
|- ( w = W -> ( w ` ( ( ( # ` w ) - 1 ) - x ) ) = ( W ` ( ( ( # ` W ) - 1 ) - x ) ) ) |
8 |
3 7
|
mpteq12dv |
|- ( w = W -> ( x e. ( 0 ..^ ( # ` w ) ) |-> ( w ` ( ( ( # ` w ) - 1 ) - x ) ) ) = ( x e. ( 0 ..^ ( # ` W ) ) |-> ( W ` ( ( ( # ` W ) - 1 ) - x ) ) ) ) |
9 |
|
df-reverse |
|- reverse = ( w e. _V |-> ( x e. ( 0 ..^ ( # ` w ) ) |-> ( w ` ( ( ( # ` w ) - 1 ) - x ) ) ) ) |
10 |
|
ovex |
|- ( 0 ..^ ( # ` W ) ) e. _V |
11 |
10
|
mptex |
|- ( x e. ( 0 ..^ ( # ` W ) ) |-> ( W ` ( ( ( # ` W ) - 1 ) - x ) ) ) e. _V |
12 |
8 9 11
|
fvmpt |
|- ( W e. _V -> ( reverse ` W ) = ( x e. ( 0 ..^ ( # ` W ) ) |-> ( W ` ( ( ( # ` W ) - 1 ) - x ) ) ) ) |
13 |
1 12
|
syl |
|- ( W e. V -> ( reverse ` W ) = ( x e. ( 0 ..^ ( # ` W ) ) |-> ( W ` ( ( ( # ` W ) - 1 ) - x ) ) ) ) |