| Step |
Hyp |
Ref |
Expression |
| 1 |
|
zaddablx.g |
|- G = { <. 1 , ZZ >. , <. 2 , + >. } |
| 2 |
|
zex |
|- ZZ e. _V |
| 3 |
|
addex |
|- + e. _V |
| 4 |
|
zaddcl |
|- ( ( x e. ZZ /\ y e. ZZ ) -> ( x + y ) e. ZZ ) |
| 5 |
|
zcn |
|- ( x e. ZZ -> x e. CC ) |
| 6 |
|
zcn |
|- ( y e. ZZ -> y e. CC ) |
| 7 |
|
zcn |
|- ( z e. ZZ -> z e. CC ) |
| 8 |
|
addass |
|- ( ( x e. CC /\ y e. CC /\ z e. CC ) -> ( ( x + y ) + z ) = ( x + ( y + z ) ) ) |
| 9 |
5 6 7 8
|
syl3an |
|- ( ( x e. ZZ /\ y e. ZZ /\ z e. ZZ ) -> ( ( x + y ) + z ) = ( x + ( y + z ) ) ) |
| 10 |
|
0z |
|- 0 e. ZZ |
| 11 |
5
|
addlidd |
|- ( x e. ZZ -> ( 0 + x ) = x ) |
| 12 |
|
znegcl |
|- ( x e. ZZ -> -u x e. ZZ ) |
| 13 |
|
zcn |
|- ( -u x e. ZZ -> -u x e. CC ) |
| 14 |
|
addcom |
|- ( ( x e. CC /\ -u x e. CC ) -> ( x + -u x ) = ( -u x + x ) ) |
| 15 |
5 13 14
|
syl2an |
|- ( ( x e. ZZ /\ -u x e. ZZ ) -> ( x + -u x ) = ( -u x + x ) ) |
| 16 |
12 15
|
mpdan |
|- ( x e. ZZ -> ( x + -u x ) = ( -u x + x ) ) |
| 17 |
5
|
negidd |
|- ( x e. ZZ -> ( x + -u x ) = 0 ) |
| 18 |
16 17
|
eqtr3d |
|- ( x e. ZZ -> ( -u x + x ) = 0 ) |
| 19 |
2 3 1 4 9 10 11 12 18
|
isgrpix |
|- G e. Grp |
| 20 |
2 3 1
|
grpbasex |
|- ZZ = ( Base ` G ) |
| 21 |
2 3 1
|
grpplusgx |
|- + = ( +g ` G ) |
| 22 |
|
addcom |
|- ( ( x e. CC /\ y e. CC ) -> ( x + y ) = ( y + x ) ) |
| 23 |
5 6 22
|
syl2an |
|- ( ( x e. ZZ /\ y e. ZZ ) -> ( x + y ) = ( y + x ) ) |
| 24 |
19 20 21 23
|
isabli |
|- G e. Abel |