Description: A polarity is a closed projective subspace. (Contributed by NM, 24-Jan-2012) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypotheses | polsubcl.a | |
|
polsubcl.p | |
||
polsubcl.c | |
||
Assertion | polsubclN | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | polsubcl.a | |
|
2 | polsubcl.p | |
|
3 | polsubcl.c | |
|
4 | eqid | |
|
5 | eqid | |
|
6 | eqid | |
|
7 | 4 5 1 6 2 | polval2N | |
8 | hlop | |
|
9 | 8 | adantr | |
10 | hlclat | |
|
11 | eqid | |
|
12 | 11 1 | atssbase | |
13 | sstr | |
|
14 | 12 13 | mpan2 | |
15 | 11 4 | clatlubcl | |
16 | 10 14 15 | syl2an | |
17 | 11 5 | opoccl | |
18 | 9 16 17 | syl2anc | |
19 | 11 6 3 | pmapsubclN | |
20 | 18 19 | syldan | |
21 | 7 20 | eqeltrd | |