Step |
Hyp |
Ref |
Expression |
1 |
|
negcl |
|
2 |
|
cxpadd |
|
3 |
1 2
|
syl3an3 |
|
4 |
|
simp2 |
|
5 |
|
simp3 |
|
6 |
4 5
|
negsubd |
|
7 |
6
|
oveq2d |
|
8 |
|
simp1l |
|
9 |
|
simp1r |
|
10 |
|
cxpneg |
|
11 |
8 9 5 10
|
syl3anc |
|
12 |
11
|
oveq2d |
|
13 |
|
cxpcl |
|
14 |
8 4 13
|
syl2anc |
|
15 |
|
cxpcl |
|
16 |
8 5 15
|
syl2anc |
|
17 |
|
cxpne0 |
|
18 |
8 9 5 17
|
syl3anc |
|
19 |
14 16 18
|
divrecd |
|
20 |
12 19
|
eqtr4d |
|
21 |
3 7 20
|
3eqtr3d |
|