Step |
Hyp |
Ref |
Expression |
1 |
|
nne |
|
2 |
|
neeq1 |
|
3 |
2
|
biimprcd |
|
4 |
1 3
|
syl5bi |
|
5 |
4
|
orrd |
|
6 |
|
inss1 |
|
7 |
6
|
jctl |
|
8 |
|
inss2 |
|
9 |
8
|
jctl |
|
10 |
7 9
|
orim12i |
|
11 |
5 10
|
syl |
|
12 |
|
inidm |
|
13 |
|
ineq2 |
|
14 |
12 13
|
syl5reqr |
|
15 |
14
|
necon3i |
|
16 |
15
|
adantl |
|
17 |
|
ineq1 |
|
18 |
|
inidm |
|
19 |
17 18
|
eqtrdi |
|
20 |
19
|
necon3i |
|
21 |
20
|
adantl |
|
22 |
16 21
|
jaoi |
|
23 |
11 22
|
impbii |
|
24 |
|
df-pss |
|
25 |
|
df-pss |
|
26 |
24 25
|
orbi12i |
|
27 |
23 26
|
bitr4i |
|