Step |
Hyp |
Ref |
Expression |
1 |
|
psubclset.a |
|
2 |
|
psubclset.p |
|
3 |
|
psubclset.c |
|
4 |
|
elex |
|
5 |
|
fveq2 |
|
6 |
5 1
|
eqtr4di |
|
7 |
6
|
sseq2d |
|
8 |
|
fveq2 |
|
9 |
8 2
|
eqtr4di |
|
10 |
9
|
fveq1d |
|
11 |
9 10
|
fveq12d |
|
12 |
11
|
eqeq1d |
|
13 |
7 12
|
anbi12d |
|
14 |
13
|
abbidv |
|
15 |
|
df-psubclN |
|
16 |
1
|
fvexi |
|
17 |
16
|
pwex |
|
18 |
|
velpw |
|
19 |
18
|
anbi1i |
|
20 |
19
|
abbii |
|
21 |
|
ssab2 |
|
22 |
20 21
|
eqsstrri |
|
23 |
17 22
|
ssexi |
|
24 |
14 15 23
|
fvmpt |
|
25 |
3 24
|
eqtrid |
|
26 |
4 25
|
syl |
|