Step |
Hyp |
Ref |
Expression |
1 |
|
peano1 |
|- (/) e. _om |
2 |
1
|
a1i |
|- ( ( A e. V /\ B e. W ) -> (/) e. _om ) |
3 |
|
1onn |
|- 1o e. _om |
4 |
3
|
a1i |
|- ( ( A e. V /\ B e. W ) -> 1o e. _om ) |
5 |
|
simpl |
|- ( ( A e. V /\ B e. W ) -> A e. V ) |
6 |
|
simpr |
|- ( ( A e. V /\ B e. W ) -> B e. W ) |
7 |
|
1n0 |
|- 1o =/= (/) |
8 |
7
|
necomi |
|- (/) =/= 1o |
9 |
8
|
a1i |
|- ( ( A e. V /\ B e. W ) -> (/) =/= 1o ) |
10 |
|
fnprg |
|- ( ( ( (/) e. _om /\ 1o e. _om ) /\ ( A e. V /\ B e. W ) /\ (/) =/= 1o ) -> { <. (/) , A >. , <. 1o , B >. } Fn { (/) , 1o } ) |
11 |
2 4 5 6 9 10
|
syl221anc |
|- ( ( A e. V /\ B e. W ) -> { <. (/) , A >. , <. 1o , B >. } Fn { (/) , 1o } ) |
12 |
|
df2o3 |
|- 2o = { (/) , 1o } |
13 |
12
|
fneq2i |
|- ( { <. (/) , A >. , <. 1o , B >. } Fn 2o <-> { <. (/) , A >. , <. 1o , B >. } Fn { (/) , 1o } ) |
14 |
11 13
|
sylibr |
|- ( ( A e. V /\ B e. W ) -> { <. (/) , A >. , <. 1o , B >. } Fn 2o ) |