Step |
Hyp |
Ref |
Expression |
1 |
|
2itscp.a |
|
2 |
|
2itscp.b |
|
3 |
|
2itscp.x |
|
4 |
|
2itscp.y |
|
5 |
|
2itscp.d |
|
6 |
|
2itscp.e |
|
7 |
|
2itscp.c |
|
8 |
7
|
oveq1i |
|
9 |
8
|
a1i |
|
10 |
3
|
recnd |
|
11 |
1
|
recnd |
|
12 |
10 11
|
subcld |
|
13 |
5 12
|
eqeltrid |
|
14 |
2
|
recnd |
|
15 |
13 14
|
mulcld |
|
16 |
4
|
recnd |
|
17 |
14 16
|
subcld |
|
18 |
6 17
|
eqeltrid |
|
19 |
18 11
|
mulcld |
|
20 |
|
binom2 |
|
21 |
15 19 20
|
syl2anc |
|
22 |
13 14
|
sqmuld |
|
23 |
|
mul4r |
|
24 |
13 14 18 11 23
|
syl22anc |
|
25 |
24
|
oveq2d |
|
26 |
22 25
|
oveq12d |
|
27 |
18 11
|
sqmuld |
|
28 |
26 27
|
oveq12d |
|
29 |
9 21 28
|
3eqtrd |
|