Description: Membership in a negated closed real interval. (Contributed by Paul Chapman, 26-Nov-2007)
Ref | Expression | ||
---|---|---|---|
Assertion | iccneg | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | renegcl | |
|
2 | ax-1 | |
|
3 | 1 2 | impbid2 | |
4 | 3 | 3ad2ant3 | |
5 | ancom | |
|
6 | leneg | |
|
7 | 6 | ancoms | |
8 | 7 | 3adant1 | |
9 | leneg | |
|
10 | 9 | 3adant2 | |
11 | 8 10 | anbi12d | |
12 | 5 11 | bitr3id | |
13 | 4 12 | anbi12d | |
14 | elicc2 | |
|
15 | 14 | 3adant3 | |
16 | 3anass | |
|
17 | 15 16 | bitrdi | |
18 | renegcl | |
|
19 | renegcl | |
|
20 | elicc2 | |
|
21 | 18 19 20 | syl2anr | |
22 | 21 | 3adant3 | |
23 | 3anass | |
|
24 | 22 23 | bitrdi | |
25 | 13 17 24 | 3bitr4d | |