Step |
Hyp |
Ref |
Expression |
1 |
|
simpr |
|- ( ( W e. Word A /\ F : A --> B ) -> F : A --> B ) |
2 |
|
wrdf |
|- ( W e. Word A -> W : ( 0 ..^ ( # ` W ) ) --> A ) |
3 |
2
|
adantr |
|- ( ( W e. Word A /\ F : A --> B ) -> W : ( 0 ..^ ( # ` W ) ) --> A ) |
4 |
|
fco |
|- ( ( F : A --> B /\ W : ( 0 ..^ ( # ` W ) ) --> A ) -> ( F o. W ) : ( 0 ..^ ( # ` W ) ) --> B ) |
5 |
1 3 4
|
syl2anc |
|- ( ( W e. Word A /\ F : A --> B ) -> ( F o. W ) : ( 0 ..^ ( # ` W ) ) --> B ) |
6 |
|
iswrdi |
|- ( ( F o. W ) : ( 0 ..^ ( # ` W ) ) --> B -> ( F o. W ) e. Word B ) |
7 |
5 6
|
syl |
|- ( ( W e. Word A /\ F : A --> B ) -> ( F o. W ) e. Word B ) |