Step |
Hyp |
Ref |
Expression |
1 |
|
ax-his2 |
|
2 |
1
|
fveq2d |
|
3 |
|
hicl |
|
4 |
|
hicl |
|
5 |
|
cjadd |
|
6 |
3 4 5
|
syl2an |
|
7 |
6
|
3impdir |
|
8 |
2 7
|
eqtrd |
|
9 |
8
|
3comr |
|
10 |
|
hvaddcl |
|
11 |
|
ax-his1 |
|
12 |
10 11
|
sylan2 |
|
13 |
12
|
3impb |
|
14 |
|
ax-his1 |
|
15 |
14
|
3adant3 |
|
16 |
|
ax-his1 |
|
17 |
16
|
3adant2 |
|
18 |
15 17
|
oveq12d |
|
19 |
9 13 18
|
3eqtr4d |
|