Step |
Hyp |
Ref |
Expression |
1 |
|
ringnegmul.1 |
|
2 |
|
ringnegmul.2 |
|
3 |
|
ringnegmul.3 |
|
4 |
|
ringnegmul.4 |
|
5 |
1
|
rneqi |
|
6 |
3 5
|
eqtri |
|
7 |
|
eqid |
|
8 |
6 2 7
|
rngo1cl |
|
9 |
1 3 4
|
rngonegcl |
|
10 |
8 9
|
mpdan |
|
11 |
1 2 3
|
rngoass |
|
12 |
11
|
3exp2 |
|
13 |
12
|
com24 |
|
14 |
13
|
com34 |
|
15 |
10 14
|
mpd |
|
16 |
15
|
3imp |
|
17 |
1 2 3
|
rngocl |
|
18 |
17
|
3expb |
|
19 |
1 2 3 4 7
|
rngonegmn1r |
|
20 |
18 19
|
syldan |
|
21 |
20
|
3impb |
|
22 |
1 2 3 4 7
|
rngonegmn1r |
|
23 |
22
|
3adant2 |
|
24 |
23
|
oveq2d |
|
25 |
16 21 24
|
3eqtr4d |
|