Step |
Hyp |
Ref |
Expression |
1 |
|
eqg0el.1 |
|
2 |
|
eqid |
|
3 |
2 1
|
eqger |
|
4 |
3
|
adantl |
|
5 |
|
eqid |
|
6 |
2 5
|
grpidcl |
|
7 |
6
|
adantr |
|
8 |
4 7
|
erth |
|
9 |
2 1 5
|
eqgid |
|
10 |
9
|
adantl |
|
11 |
10
|
eqeq1d |
|
12 |
|
eqcom |
|
13 |
12
|
a1i |
|
14 |
8 11 13
|
3bitrrd |
|
15 |
|
errel |
|
16 |
|
relelec |
|
17 |
3 15 16
|
3syl |
|
18 |
17
|
adantl |
|
19 |
10
|
eleq2d |
|
20 |
14 18 19
|
3bitr2d |
|