Step |
Hyp |
Ref |
Expression |
1 |
|
neg1cn |
|
2 |
|
homulcl |
|
3 |
1 2
|
mpan |
|
4 |
|
hoadddi |
|
5 |
3 4
|
syl3an3 |
|
6 |
|
homul12 |
|
7 |
1 6
|
mp3an2 |
|
8 |
7
|
3adant2 |
|
9 |
8
|
oveq2d |
|
10 |
5 9
|
eqtrd |
|
11 |
|
honegsub |
|
12 |
11
|
oveq2d |
|
13 |
12
|
3adant1 |
|
14 |
|
homulcl |
|
15 |
|
homulcl |
|
16 |
|
honegsub |
|
17 |
14 15 16
|
syl2an |
|
18 |
17
|
3impdi |
|
19 |
10 13 18
|
3eqtr3d |
|