Step |
Hyp |
Ref |
Expression |
1 |
|
dfac5lem.1 |
|
2 |
1
|
unieqi |
|
3 |
2
|
eleq2i |
|
4 |
|
eluniab |
|
5 |
|
r19.42v |
|
6 |
|
anass |
|
7 |
5 6
|
bitr2i |
|
8 |
7
|
exbii |
|
9 |
|
rexcom4 |
|
10 |
|
df-rex |
|
11 |
9 10
|
bitr3i |
|
12 |
4 8 11
|
3bitri |
|
13 |
|
ancom |
|
14 |
|
ne0i |
|
15 |
14
|
pm4.71i |
|
16 |
15
|
anbi2i |
|
17 |
13 16
|
bitr4i |
|
18 |
17
|
exbii |
|
19 |
|
snex |
|
20 |
|
vex |
|
21 |
19 20
|
xpex |
|
22 |
|
eleq2 |
|
23 |
21 22
|
ceqsexv |
|
24 |
18 23
|
bitri |
|
25 |
24
|
anbi2i |
|
26 |
|
opelxp |
|
27 |
|
velsn |
|
28 |
|
equcom |
|
29 |
27 28
|
bitri |
|
30 |
29
|
anbi1i |
|
31 |
26 30
|
bitri |
|
32 |
31
|
anbi2i |
|
33 |
|
an12 |
|
34 |
25 32 33
|
3bitri |
|
35 |
34
|
exbii |
|
36 |
|
vex |
|
37 |
|
elequ1 |
|
38 |
|
eleq2 |
|
39 |
37 38
|
anbi12d |
|
40 |
36 39
|
ceqsexv |
|
41 |
35 40
|
bitri |
|
42 |
3 12 41
|
3bitri |
|