Step |
Hyp |
Ref |
Expression |
1 |
|
3optocl.1 |
|- R = ( D X. F ) |
2 |
|
3optocl.2 |
|- ( <. x , y >. = A -> ( ph <-> ps ) ) |
3 |
|
3optocl.3 |
|- ( <. z , w >. = B -> ( ps <-> ch ) ) |
4 |
|
3optocl.4 |
|- ( <. v , u >. = C -> ( ch <-> th ) ) |
5 |
|
3optocl.5 |
|- ( ( ( x e. D /\ y e. F ) /\ ( z e. D /\ w e. F ) /\ ( v e. D /\ u e. F ) ) -> ph ) |
6 |
4
|
imbi2d |
|- ( <. v , u >. = C -> ( ( ( A e. R /\ B e. R ) -> ch ) <-> ( ( A e. R /\ B e. R ) -> th ) ) ) |
7 |
2
|
imbi2d |
|- ( <. x , y >. = A -> ( ( ( v e. D /\ u e. F ) -> ph ) <-> ( ( v e. D /\ u e. F ) -> ps ) ) ) |
8 |
3
|
imbi2d |
|- ( <. z , w >. = B -> ( ( ( v e. D /\ u e. F ) -> ps ) <-> ( ( v e. D /\ u e. F ) -> ch ) ) ) |
9 |
5
|
3expia |
|- ( ( ( x e. D /\ y e. F ) /\ ( z e. D /\ w e. F ) ) -> ( ( v e. D /\ u e. F ) -> ph ) ) |
10 |
1 7 8 9
|
2optocl |
|- ( ( A e. R /\ B e. R ) -> ( ( v e. D /\ u e. F ) -> ch ) ) |
11 |
10
|
com12 |
|- ( ( v e. D /\ u e. F ) -> ( ( A e. R /\ B e. R ) -> ch ) ) |
12 |
1 6 11
|
optocl |
|- ( C e. R -> ( ( A e. R /\ B e. R ) -> th ) ) |
13 |
12
|
impcom |
|- ( ( ( A e. R /\ B e. R ) /\ C e. R ) -> th ) |
14 |
13
|
3impa |
|- ( ( A e. R /\ B e. R /\ C e. R ) -> th ) |