| 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 |
|
vsnex |
|
| 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 |
|