Step |
Hyp |
Ref |
Expression |
1 |
|
cbvraldva2.1 |
|
2 |
|
cbvraldva2.2 |
|
3 |
|
simpr |
|
4 |
3 2
|
eleq12d |
|
5 |
4 1
|
anbi12d |
|
6 |
5
|
notbid |
|
7 |
6
|
expcom |
|
8 |
7
|
pm5.74d |
|
9 |
8
|
cbvalvw |
|
10 |
|
19.21v |
|
11 |
|
19.21v |
|
12 |
9 10 11
|
3bitr3i |
|
13 |
12
|
pm5.74ri |
|
14 |
|
alnex |
|
15 |
|
alnex |
|
16 |
13 14 15
|
3bitr3g |
|
17 |
16
|
con4bid |
|
18 |
|
df-rex |
|
19 |
|
df-rex |
|
20 |
17 18 19
|
3bitr4g |
|