Description: Given a topology J , show that a subset B satisfying the third antecedent is a basis for it. Lemma 2.3 of Munkres p. 81 using abbreviations. (Contributed by NM, 22-Jul-2006) (Revised by Mario Carneiro, 2-Sep-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | basgen | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | tgss | |
|
2 | 1 | 3adant3 | |
3 | tgtop | |
|
4 | 3 | 3ad2ant1 | |
5 | 2 4 | sseqtrd | |
6 | simp3 | |
|
7 | 5 6 | eqssd | |