Description: An ideal is closed under negation. (Contributed by Jeff Madsen, 10-Jun-2010)
Ref | Expression | ||
---|---|---|---|
Hypotheses | idlnegcl.1 | |
|
idlnegcl.2 | |
||
Assertion | idlnegcl | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | idlnegcl.1 | |
|
2 | idlnegcl.2 | |
|
3 | eqid | |
|
4 | 1 3 | idlss | |
5 | ssel2 | |
|
6 | eqid | |
|
7 | eqid | |
|
8 | 1 6 3 2 7 | rngonegmn1l | |
9 | 5 8 | sylan2 | |
10 | 9 | anassrs | |
11 | 4 10 | syldanl | |
12 | 1 | rneqi | |
13 | 12 6 7 | rngo1cl | |
14 | 1 3 2 | rngonegcl | |
15 | 13 14 | mpdan | |
16 | 15 | ad2antrr | |
17 | 1 6 3 | idllmulcl | |
18 | 17 | anassrs | |
19 | 16 18 | mpdan | |
20 | 11 19 | eqeltrd | |