Step |
Hyp |
Ref |
Expression |
1 |
|
isconngr.v |
|
2 |
|
dfconngr1 |
|
3 |
2
|
eleq2i |
|
4 |
|
fvex |
|
5 |
|
id |
|
6 |
|
difeq1 |
|
7 |
6
|
raleqdv |
|
8 |
5 7
|
raleqbidv |
|
9 |
4 8
|
sbcie |
|
10 |
9
|
abbii |
|
11 |
10
|
eleq2i |
|
12 |
|
fveq2 |
|
13 |
12 1
|
eqtr4di |
|
14 |
13
|
difeq1d |
|
15 |
|
fveq2 |
|
16 |
15
|
oveqd |
|
17 |
16
|
breqd |
|
18 |
17
|
2exbidv |
|
19 |
14 18
|
raleqbidv |
|
20 |
13 19
|
raleqbidv |
|
21 |
|
fveq2 |
|
22 |
21
|
difeq1d |
|
23 |
|
fveq2 |
|
24 |
23
|
oveqd |
|
25 |
24
|
breqd |
|
26 |
25
|
2exbidv |
|
27 |
22 26
|
raleqbidv |
|
28 |
21 27
|
raleqbidv |
|
29 |
28
|
cbvabv |
|
30 |
20 29
|
elab2g |
|
31 |
11 30
|
syl5bb |
|
32 |
3 31
|
syl5bb |
|