Description: The inverse of a group element expressed in terms of the identity element. (Contributed by NM, 27-Oct-2006) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypotheses | grpinv.1 | |
|
grpinv.2 | |
||
grpinv.3 | |
||
Assertion | grpoinvid1 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | grpinv.1 | |
|
2 | grpinv.2 | |
|
3 | grpinv.3 | |
|
4 | oveq2 | |
|
5 | 4 | adantl | |
6 | 1 2 3 | grporinv | |
7 | 6 | 3adant3 | |
8 | 7 | adantr | |
9 | 5 8 | eqtr3d | |
10 | oveq2 | |
|
11 | 10 | adantl | |
12 | 1 2 3 | grpolinv | |
13 | 12 | oveq1d | |
14 | 13 | 3adant3 | |
15 | 1 3 | grpoinvcl | |
16 | 15 | adantrr | |
17 | simprl | |
|
18 | simprr | |
|
19 | 16 17 18 | 3jca | |
20 | 1 | grpoass | |
21 | 19 20 | syldan | |
22 | 21 | 3impb | |
23 | 14 22 | eqtr3d | |
24 | 1 2 | grpolid | |
25 | 24 | 3adant2 | |
26 | 23 25 | eqtr3d | |
27 | 26 | adantr | |
28 | 1 2 | grporid | |
29 | 15 28 | syldan | |
30 | 29 | 3adant3 | |
31 | 30 | adantr | |
32 | 11 27 31 | 3eqtr3rd | |
33 | 9 32 | impbida | |