Description: Define the quotient topology given a function f and topology j on the domain of f . (Contributed by Mario Carneiro, 23-Mar-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | df-qtop | |- qTop = ( j e. _V , f e. _V |-> { s e. ~P ( f " U. j ) | ( ( `' f " s ) i^i U. j ) e. j } ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
0 | cqtop | |- qTop |
|
1 | vj | |- j |
|
2 | cvv | |- _V |
|
3 | vf | |- f |
|
4 | vs | |- s |
|
5 | 3 | cv | |- f |
6 | 1 | cv | |- j |
7 | 6 | cuni | |- U. j |
8 | 5 7 | cima | |- ( f " U. j ) |
9 | 8 | cpw | |- ~P ( f " U. j ) |
10 | 5 | ccnv | |- `' f |
11 | 4 | cv | |- s |
12 | 10 11 | cima | |- ( `' f " s ) |
13 | 12 7 | cin | |- ( ( `' f " s ) i^i U. j ) |
14 | 13 6 | wcel | |- ( ( `' f " s ) i^i U. j ) e. j |
15 | 14 4 9 | crab | |- { s e. ~P ( f " U. j ) | ( ( `' f " s ) i^i U. j ) e. j } |
16 | 1 3 2 2 15 | cmpo | |- ( j e. _V , f e. _V |-> { s e. ~P ( f " U. j ) | ( ( `' f " s ) i^i U. j ) e. j } ) |
17 | 0 16 | wceq | |- qTop = ( j e. _V , f e. _V |-> { s e. ~P ( f " U. j ) | ( ( `' f " s ) i^i U. j ) e. j } ) |