Step |
Hyp |
Ref |
Expression |
1 |
|
mulgsubdir.b |
|
2 |
|
mulgsubdir.t |
|
3 |
|
mulgsubdir.d |
|
4 |
|
znegcl |
|
5 |
|
eqid |
|
6 |
1 2 5
|
mulgdir |
|
7 |
4 6
|
syl3anr2 |
|
8 |
|
simpr1 |
|
9 |
8
|
zcnd |
|
10 |
|
simpr2 |
|
11 |
10
|
zcnd |
|
12 |
9 11
|
negsubd |
|
13 |
12
|
oveq1d |
|
14 |
|
eqid |
|
15 |
1 2 14
|
mulgneg |
|
16 |
15
|
3adant3r1 |
|
17 |
16
|
oveq2d |
|
18 |
1 2
|
mulgcl |
|
19 |
18
|
3adant3r2 |
|
20 |
1 2
|
mulgcl |
|
21 |
20
|
3adant3r1 |
|
22 |
1 5 14 3
|
grpsubval |
|
23 |
19 21 22
|
syl2anc |
|
24 |
17 23
|
eqtr4d |
|
25 |
7 13 24
|
3eqtr3d |
|