Step |
Hyp |
Ref |
Expression |
1 |
|
simpl |
|- ( ( x e. ZZ /\ y e. ZZ ) -> x e. ZZ ) |
2 |
1
|
anim1i |
|- ( ( ( x e. ZZ /\ y e. ZZ ) /\ E. z e. ZZ ( z x. x ) = y ) -> ( x e. ZZ /\ E. z e. ZZ ( z x. x ) = y ) ) |
3 |
|
simpl |
|- ( ( x e. ZZ /\ E. z e. ZZ ( z x. x ) = y ) -> x e. ZZ ) |
4 |
|
zmulcl |
|- ( ( z e. ZZ /\ x e. ZZ ) -> ( z x. x ) e. ZZ ) |
5 |
4
|
ancoms |
|- ( ( x e. ZZ /\ z e. ZZ ) -> ( z x. x ) e. ZZ ) |
6 |
|
eleq1 |
|- ( ( z x. x ) = y -> ( ( z x. x ) e. ZZ <-> y e. ZZ ) ) |
7 |
5 6
|
syl5ibcom |
|- ( ( x e. ZZ /\ z e. ZZ ) -> ( ( z x. x ) = y -> y e. ZZ ) ) |
8 |
7
|
rexlimdva |
|- ( x e. ZZ -> ( E. z e. ZZ ( z x. x ) = y -> y e. ZZ ) ) |
9 |
8
|
imp |
|- ( ( x e. ZZ /\ E. z e. ZZ ( z x. x ) = y ) -> y e. ZZ ) |
10 |
|
simpr |
|- ( ( x e. ZZ /\ E. z e. ZZ ( z x. x ) = y ) -> E. z e. ZZ ( z x. x ) = y ) |
11 |
3 9 10
|
jca31 |
|- ( ( x e. ZZ /\ E. z e. ZZ ( z x. x ) = y ) -> ( ( x e. ZZ /\ y e. ZZ ) /\ E. z e. ZZ ( z x. x ) = y ) ) |
12 |
2 11
|
impbii |
|- ( ( ( x e. ZZ /\ y e. ZZ ) /\ E. z e. ZZ ( z x. x ) = y ) <-> ( x e. ZZ /\ E. z e. ZZ ( z x. x ) = y ) ) |
13 |
12
|
opabbii |
|- { <. x , y >. | ( ( x e. ZZ /\ y e. ZZ ) /\ E. z e. ZZ ( z x. x ) = y ) } = { <. x , y >. | ( x e. ZZ /\ E. z e. ZZ ( z x. x ) = y ) } |
14 |
|
df-dvds |
|- || = { <. x , y >. | ( ( x e. ZZ /\ y e. ZZ ) /\ E. z e. ZZ ( z x. x ) = y ) } |
15 |
|
zringbas |
|- ZZ = ( Base ` ZZring ) |
16 |
|
eqid |
|- ( ||r ` ZZring ) = ( ||r ` ZZring ) |
17 |
|
zringmulr |
|- x. = ( .r ` ZZring ) |
18 |
15 16 17
|
dvdsrval |
|- ( ||r ` ZZring ) = { <. x , y >. | ( x e. ZZ /\ E. z e. ZZ ( z x. x ) = y ) } |
19 |
13 14 18
|
3eqtr4i |
|- || = ( ||r ` ZZring ) |