Step |
Hyp |
Ref |
Expression |
1 |
|
unitsubm.1 |
|
2 |
|
unitsubm.2 |
|
3 |
|
eqid |
|
4 |
3 1
|
unitss |
|
5 |
4
|
a1i |
|
6 |
|
eqid |
|
7 |
1 6
|
1unit |
|
8 |
2
|
oveq1i |
|
9 |
1 8
|
unitgrp |
|
10 |
|
grpmnd |
|
11 |
9 10
|
syl |
|
12 |
2
|
ringmgp |
|
13 |
2 3
|
mgpbas |
|
14 |
2 6
|
ringidval |
|
15 |
|
eqid |
|
16 |
13 14 15
|
issubm2 |
|
17 |
12 16
|
syl |
|
18 |
5 7 11 17
|
mpbir3and |
|