| Step |
Hyp |
Ref |
Expression |
| 1 |
|
opsbc2ie.a |
|- ( p = <. a , b >. -> ( ph <-> ch ) ) |
| 2 |
1
|
sbcth |
|- ( x e. _V -> [. x / a ]. ( p = <. a , b >. -> ( ph <-> ch ) ) ) |
| 3 |
|
sbcim1 |
|- ( [. x / a ]. ( p = <. a , b >. -> ( ph <-> ch ) ) -> ( [. x / a ]. p = <. a , b >. -> [. x / a ]. ( ph <-> ch ) ) ) |
| 4 |
2 3
|
syl |
|- ( x e. _V -> ( [. x / a ]. p = <. a , b >. -> [. x / a ]. ( ph <-> ch ) ) ) |
| 5 |
|
sbceq2g |
|- ( x e. _V -> ( [. x / a ]. p = <. a , b >. <-> p = [_ x / a ]_ <. a , b >. ) ) |
| 6 |
|
csbopg |
|- ( x e. _V -> [_ x / a ]_ <. a , b >. = <. [_ x / a ]_ a , [_ x / a ]_ b >. ) |
| 7 |
|
csbvarg |
|- ( x e. _V -> [_ x / a ]_ a = x ) |
| 8 |
|
csbconstg |
|- ( x e. _V -> [_ x / a ]_ b = b ) |
| 9 |
7 8
|
opeq12d |
|- ( x e. _V -> <. [_ x / a ]_ a , [_ x / a ]_ b >. = <. x , b >. ) |
| 10 |
6 9
|
eqtrd |
|- ( x e. _V -> [_ x / a ]_ <. a , b >. = <. x , b >. ) |
| 11 |
10
|
eqeq2d |
|- ( x e. _V -> ( p = [_ x / a ]_ <. a , b >. <-> p = <. x , b >. ) ) |
| 12 |
5 11
|
bitrd |
|- ( x e. _V -> ( [. x / a ]. p = <. a , b >. <-> p = <. x , b >. ) ) |
| 13 |
|
sbcbig |
|- ( x e. _V -> ( [. x / a ]. ( ph <-> ch ) <-> ( [. x / a ]. ph <-> [. x / a ]. ch ) ) ) |
| 14 |
|
sbcg |
|- ( x e. _V -> ( [. x / a ]. ph <-> ph ) ) |
| 15 |
14
|
bibi1d |
|- ( x e. _V -> ( ( [. x / a ]. ph <-> [. x / a ]. ch ) <-> ( ph <-> [. x / a ]. ch ) ) ) |
| 16 |
13 15
|
bitrd |
|- ( x e. _V -> ( [. x / a ]. ( ph <-> ch ) <-> ( ph <-> [. x / a ]. ch ) ) ) |
| 17 |
4 12 16
|
3imtr3d |
|- ( x e. _V -> ( p = <. x , b >. -> ( ph <-> [. x / a ]. ch ) ) ) |
| 18 |
17
|
elv |
|- ( p = <. x , b >. -> ( ph <-> [. x / a ]. ch ) ) |
| 19 |
18
|
sbcth |
|- ( y e. _V -> [. y / b ]. ( p = <. x , b >. -> ( ph <-> [. x / a ]. ch ) ) ) |
| 20 |
|
sbcim1 |
|- ( [. y / b ]. ( p = <. x , b >. -> ( ph <-> [. x / a ]. ch ) ) -> ( [. y / b ]. p = <. x , b >. -> [. y / b ]. ( ph <-> [. x / a ]. ch ) ) ) |
| 21 |
19 20
|
syl |
|- ( y e. _V -> ( [. y / b ]. p = <. x , b >. -> [. y / b ]. ( ph <-> [. x / a ]. ch ) ) ) |
| 22 |
|
sbceq2g |
|- ( y e. _V -> ( [. y / b ]. p = <. x , b >. <-> p = [_ y / b ]_ <. x , b >. ) ) |
| 23 |
|
csbopg |
|- ( y e. _V -> [_ y / b ]_ <. x , b >. = <. [_ y / b ]_ x , [_ y / b ]_ b >. ) |
| 24 |
|
csbconstg |
|- ( y e. _V -> [_ y / b ]_ x = x ) |
| 25 |
|
csbvarg |
|- ( y e. _V -> [_ y / b ]_ b = y ) |
| 26 |
24 25
|
opeq12d |
|- ( y e. _V -> <. [_ y / b ]_ x , [_ y / b ]_ b >. = <. x , y >. ) |
| 27 |
23 26
|
eqtrd |
|- ( y e. _V -> [_ y / b ]_ <. x , b >. = <. x , y >. ) |
| 28 |
27
|
eqeq2d |
|- ( y e. _V -> ( p = [_ y / b ]_ <. x , b >. <-> p = <. x , y >. ) ) |
| 29 |
22 28
|
bitrd |
|- ( y e. _V -> ( [. y / b ]. p = <. x , b >. <-> p = <. x , y >. ) ) |
| 30 |
|
sbcbig |
|- ( y e. _V -> ( [. y / b ]. ( ph <-> [. x / a ]. ch ) <-> ( [. y / b ]. ph <-> [. y / b ]. [. x / a ]. ch ) ) ) |
| 31 |
|
sbcg |
|- ( y e. _V -> ( [. y / b ]. ph <-> ph ) ) |
| 32 |
31
|
bibi1d |
|- ( y e. _V -> ( ( [. y / b ]. ph <-> [. y / b ]. [. x / a ]. ch ) <-> ( ph <-> [. y / b ]. [. x / a ]. ch ) ) ) |
| 33 |
30 32
|
bitrd |
|- ( y e. _V -> ( [. y / b ]. ( ph <-> [. x / a ]. ch ) <-> ( ph <-> [. y / b ]. [. x / a ]. ch ) ) ) |
| 34 |
21 29 33
|
3imtr3d |
|- ( y e. _V -> ( p = <. x , y >. -> ( ph <-> [. y / b ]. [. x / a ]. ch ) ) ) |
| 35 |
34
|
elv |
|- ( p = <. x , y >. -> ( ph <-> [. y / b ]. [. x / a ]. ch ) ) |