Step |
Hyp |
Ref |
Expression |
1 |
|
znegcl |
|
2 |
|
fzoaddel |
|
3 |
1 2
|
sylan2 |
|
4 |
|
elfzoelz |
|
5 |
4
|
adantr |
|
6 |
5
|
zcnd |
|
7 |
|
simpr |
|
8 |
7
|
zcnd |
|
9 |
6 8
|
negsubd |
|
10 |
|
elfzoel1 |
|
11 |
10
|
adantr |
|
12 |
11
|
zcnd |
|
13 |
12 8
|
negsubd |
|
14 |
|
elfzoel2 |
|
15 |
14
|
adantr |
|
16 |
15
|
zcnd |
|
17 |
16 8
|
negsubd |
|
18 |
13 17
|
oveq12d |
|
19 |
3 9 18
|
3eltr3d |
|