Description: When Line is applied with the same argument, the result is the empty set. (Contributed by Scott Fenton, 29-Oct-2013) (Revised by Mario Carneiro, 19-Apr-2014)
Ref | Expression | ||
---|---|---|---|
Assertion | linedegen | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-ov | |
|
2 | neirr | |
|
3 | simp3 | |
|
4 | 2 3 | mto | |
5 | 4 | intnanr | |
6 | 5 | a1i | |
7 | 6 | nrex | |
8 | 7 | nex | |
9 | eleq1 | |
|
10 | neeq1 | |
|
11 | 9 10 | 3anbi13d | |
12 | opeq1 | |
|
13 | 12 | eceq1d | |
14 | 13 | eqeq2d | |
15 | 11 14 | anbi12d | |
16 | 15 | rexbidv | |
17 | 16 | exbidv | |
18 | eleq1 | |
|
19 | neeq2 | |
|
20 | 18 19 | 3anbi23d | |
21 | opeq2 | |
|
22 | 21 | eceq1d | |
23 | 22 | eqeq2d | |
24 | 20 23 | anbi12d | |
25 | 24 | rexbidv | |
26 | 25 | exbidv | |
27 | 17 26 | opelopabg | |
28 | 27 | anidms | |
29 | 8 28 | mtbiri | |
30 | elopaelxp | |
|
31 | opelxp1 | |
|
32 | 30 31 | syl | |
33 | 32 | con3i | |
34 | 29 33 | pm2.61i | |
35 | df-line2 | |
|
36 | 35 | dmeqi | |
37 | dmoprab | |
|
38 | 36 37 | eqtri | |
39 | 38 | eleq2i | |
40 | 34 39 | mtbir | |
41 | ndmfv | |
|
42 | 40 41 | ax-mp | |
43 | 1 42 | eqtri | |