| Step |
Hyp |
Ref |
Expression |
| 1 |
|
ringnegmul.1 |
|- G = ( 1st ` R ) |
| 2 |
|
ringnegmul.2 |
|- H = ( 2nd ` R ) |
| 3 |
|
ringnegmul.3 |
|- X = ran G |
| 4 |
|
ringnegmul.4 |
|- N = ( inv ` G ) |
| 5 |
1
|
rneqi |
|- ran G = ran ( 1st ` R ) |
| 6 |
3 5
|
eqtri |
|- X = ran ( 1st ` R ) |
| 7 |
|
eqid |
|- ( GId ` H ) = ( GId ` H ) |
| 8 |
6 2 7
|
rngo1cl |
|- ( R e. RingOps -> ( GId ` H ) e. X ) |
| 9 |
1 3 4
|
rngonegcl |
|- ( ( R e. RingOps /\ ( GId ` H ) e. X ) -> ( N ` ( GId ` H ) ) e. X ) |
| 10 |
8 9
|
mpdan |
|- ( R e. RingOps -> ( N ` ( GId ` H ) ) e. X ) |
| 11 |
1 2 3
|
rngoass |
|- ( ( R e. RingOps /\ ( ( N ` ( GId ` H ) ) e. X /\ A e. X /\ B e. X ) ) -> ( ( ( N ` ( GId ` H ) ) H A ) H B ) = ( ( N ` ( GId ` H ) ) H ( A H B ) ) ) |
| 12 |
11
|
3exp2 |
|- ( R e. RingOps -> ( ( N ` ( GId ` H ) ) e. X -> ( A e. X -> ( B e. X -> ( ( ( N ` ( GId ` H ) ) H A ) H B ) = ( ( N ` ( GId ` H ) ) H ( A H B ) ) ) ) ) ) |
| 13 |
10 12
|
mpd |
|- ( R e. RingOps -> ( A e. X -> ( B e. X -> ( ( ( N ` ( GId ` H ) ) H A ) H B ) = ( ( N ` ( GId ` H ) ) H ( A H B ) ) ) ) ) |
| 14 |
13
|
3imp |
|- ( ( R e. RingOps /\ A e. X /\ B e. X ) -> ( ( ( N ` ( GId ` H ) ) H A ) H B ) = ( ( N ` ( GId ` H ) ) H ( A H B ) ) ) |
| 15 |
1 2 3 4 7
|
rngonegmn1l |
|- ( ( R e. RingOps /\ A e. X ) -> ( N ` A ) = ( ( N ` ( GId ` H ) ) H A ) ) |
| 16 |
15
|
3adant3 |
|- ( ( R e. RingOps /\ A e. X /\ B e. X ) -> ( N ` A ) = ( ( N ` ( GId ` H ) ) H A ) ) |
| 17 |
16
|
oveq1d |
|- ( ( R e. RingOps /\ A e. X /\ B e. X ) -> ( ( N ` A ) H B ) = ( ( ( N ` ( GId ` H ) ) H A ) H B ) ) |
| 18 |
1 2 3
|
rngocl |
|- ( ( R e. RingOps /\ A e. X /\ B e. X ) -> ( A H B ) e. X ) |
| 19 |
18
|
3expb |
|- ( ( R e. RingOps /\ ( A e. X /\ B e. X ) ) -> ( A H B ) e. X ) |
| 20 |
1 2 3 4 7
|
rngonegmn1l |
|- ( ( R e. RingOps /\ ( A H B ) e. X ) -> ( N ` ( A H B ) ) = ( ( N ` ( GId ` H ) ) H ( A H B ) ) ) |
| 21 |
19 20
|
syldan |
|- ( ( R e. RingOps /\ ( A e. X /\ B e. X ) ) -> ( N ` ( A H B ) ) = ( ( N ` ( GId ` H ) ) H ( A H B ) ) ) |
| 22 |
21
|
3impb |
|- ( ( R e. RingOps /\ A e. X /\ B e. X ) -> ( N ` ( A H B ) ) = ( ( N ` ( GId ` H ) ) H ( A H B ) ) ) |
| 23 |
14 17 22
|
3eqtr4rd |
|- ( ( R e. RingOps /\ A e. X /\ B e. X ) -> ( N ` ( A H B ) ) = ( ( N ` A ) H B ) ) |