Step |
Hyp |
Ref |
Expression |
1 |
|
ngpinvds.x |
|
2 |
|
ngpinvds.i |
|
3 |
|
ngpinvds.d |
|
4 |
|
eqid |
|
5 |
|
simplr |
|
6 |
|
simprr |
|
7 |
|
simprl |
|
8 |
1 4 2 5 6 7
|
ablsub2inv |
|
9 |
8
|
fveq2d |
|
10 |
|
simpll |
|
11 |
|
ngpgrp |
|
12 |
10 11
|
syl |
|
13 |
1 2
|
grpinvcl |
|
14 |
12 7 13
|
syl2anc |
|
15 |
1 2
|
grpinvcl |
|
16 |
12 6 15
|
syl2anc |
|
17 |
|
eqid |
|
18 |
17 1 4 3
|
ngpdsr |
|
19 |
10 14 16 18
|
syl3anc |
|
20 |
17 1 4 3
|
ngpds |
|
21 |
10 7 6 20
|
syl3anc |
|
22 |
9 19 21
|
3eqtr4d |
|