Step |
Hyp |
Ref |
Expression |
1 |
|
cnaddabl.g |
|
2 |
|
cnex |
|
3 |
1
|
grpbase |
|
4 |
2 3
|
ax-mp |
|
5 |
|
addex |
|
6 |
1
|
grpplusg |
|
7 |
5 6
|
ax-mp |
|
8 |
|
addcl |
|
9 |
|
addass |
|
10 |
|
0cn |
|
11 |
|
addid2 |
|
12 |
|
negcl |
|
13 |
|
addcom |
|
14 |
12 13
|
mpdan |
|
15 |
|
negid |
|
16 |
14 15
|
eqtr3d |
|
17 |
4 7 8 9 10 11 12 16
|
isgrpi |
|
18 |
|
addcom |
|
19 |
17 4 7 18
|
isabli |
|