Step |
Hyp |
Ref |
Expression |
1 |
|
df-fun |
|
2 |
|
cotrg |
|
3 |
|
breq1 |
|
4 |
3
|
anbi1d |
|
5 |
|
breq1 |
|
6 |
4 5
|
imbi12d |
|
7 |
6
|
albidv |
|
8 |
|
breq2 |
|
9 |
|
breq1 |
|
10 |
8 9
|
anbi12d |
|
11 |
10
|
imbi1d |
|
12 |
11
|
albidv |
|
13 |
7 12
|
alcomw |
|
14 |
|
vex |
|
15 |
|
vex |
|
16 |
14 15
|
brcnv |
|
17 |
16
|
anbi1i |
|
18 |
|
vex |
|
19 |
18
|
ideq |
|
20 |
17 19
|
imbi12i |
|
21 |
20
|
3albii |
|
22 |
13 21
|
bitri |
|
23 |
2 22
|
bitri |
|
24 |
23
|
anbi2i |
|
25 |
1 24
|
bitri |
|