Description: The polarity of the singleton of an atom (i.e. a point). (Contributed by NM, 14-Jan-2012) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypotheses | polat.o | |
|
polat.a | |
||
polat.m | |
||
polat.p | |
||
Assertion | polatN | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | polat.o | |
|
2 | polat.a | |
|
3 | polat.m | |
|
4 | polat.p | |
|
5 | snssi | |
|
6 | 1 2 3 4 | polvalN | |
7 | 5 6 | sylan2 | |
8 | 2fveq3 | |
|
9 | 8 | iinxsng | |
10 | 9 | adantl | |
11 | 10 | ineq2d | |
12 | olop | |
|
13 | eqid | |
|
14 | 13 2 | atbase | |
15 | 13 1 | opoccl | |
16 | 12 14 15 | syl2an | |
17 | 13 2 3 | pmapssat | |
18 | 16 17 | syldan | |
19 | sseqin2 | |
|
20 | 18 19 | sylib | |
21 | 7 11 20 | 3eqtrd | |