Step |
Hyp |
Ref |
Expression |
1 |
|
cnvco |
|
2 |
|
cnvss |
|
3 |
1 2
|
eqsstrrid |
|
4 |
|
cnvco |
|
5 |
|
cnvss |
|
6 |
|
sseq1 |
|
7 |
|
dfrel2 |
|
8 |
7
|
biimpi |
|
9 |
8
|
3ad2ant1 |
|
10 |
|
dfrel2 |
|
11 |
10
|
biimpi |
|
12 |
11
|
3ad2ant2 |
|
13 |
9 12
|
coeq12d |
|
14 |
|
dfrel2 |
|
15 |
14
|
biimpi |
|
16 |
15
|
3ad2ant3 |
|
17 |
13 16
|
sseq12d |
|
18 |
17
|
biimpcd |
|
19 |
6 18
|
syl6bi |
|
20 |
4 5 19
|
mpsyl |
|
21 |
20
|
com12 |
|
22 |
3 21
|
impbid2 |
|