Description: Virtual deduction proof of elex22 . (Contributed by Alan Sare, 24-Oct-2011) (Proof modification is discouraged.) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | elex22VD | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | idn1 | |
|
2 | simpl | |
|
3 | 1 2 | e1a | |
4 | elisset | |
|
5 | 3 4 | e1a | |
6 | idn2 | |
|
7 | eleq1a | |
|
8 | 3 6 7 | e12 | |
9 | simpr | |
|
10 | 1 9 | e1a | |
11 | eleq1a | |
|
12 | 10 6 11 | e12 | |
13 | pm3.2 | |
|
14 | 8 12 13 | e22 | |
15 | 14 | in2 | |
16 | 15 | gen11 | |
17 | exim | |
|
18 | 16 17 | e1a | |
19 | pm2.27 | |
|
20 | 5 18 19 | e11 | |
21 | 20 | in1 | |