Step |
Hyp |
Ref |
Expression |
1 |
|
sbid |
|
2 |
|
drsb2 |
|
3 |
1 2
|
bitr3id |
|
4 |
|
sbid |
|
5 |
|
drsb2 |
|
6 |
4 5
|
bitr3id |
|
7 |
6
|
dral2 |
|
8 |
3 7
|
bitr3d |
|
9 |
8
|
adantl |
|
10 |
|
sb4b |
|
11 |
10
|
adantl |
|
12 |
|
nfnae |
|
13 |
|
sb4b |
|
14 |
12 13
|
albid |
|
15 |
|
alcom |
|
16 |
14 15
|
bitrdi |
|
17 |
|
nfnae |
|
18 |
|
nfeqf1 |
|
19 |
|
19.21t |
|
20 |
18 19
|
syl |
|
21 |
17 20
|
albid |
|
22 |
16 21
|
sylan9bbr |
|
23 |
11 22
|
bitr4d |
|
24 |
9 23
|
pm2.61dan |
|