Step | Hyp | Ref
| Expression |
1 | | cnvresid 6628 |
. . . . . . 7
β’ β‘( I βΎ π) = ( I βΎ π) |
2 | 1 | imaeq1i 6057 |
. . . . . 6
β’ (β‘( I βΎ π) β π₯) = (( I βΎ π) β π₯) |
3 | | resiima 6076 |
. . . . . . 7
β’ (π₯ β π β (( I βΎ π) β π₯) = π₯) |
4 | 3 | adantl 483 |
. . . . . 6
β’ ((π½ β (TopOnβπ) β§ π₯ β π) β (( I βΎ π) β π₯) = π₯) |
5 | 2, 4 | eqtrid 2785 |
. . . . 5
β’ ((π½ β (TopOnβπ) β§ π₯ β π) β (β‘( I βΎ π) β π₯) = π₯) |
6 | 5 | eleq1d 2819 |
. . . 4
β’ ((π½ β (TopOnβπ) β§ π₯ β π) β ((β‘( I βΎ π) β π₯) β π½ β π₯ β π½)) |
7 | 6 | pm5.32da 580 |
. . 3
β’ (π½ β (TopOnβπ) β ((π₯ β π β§ (β‘( I βΎ π) β π₯) β π½) β (π₯ β π β§ π₯ β π½))) |
8 | | f1oi 6872 |
. . . . 5
β’ ( I
βΎ π):πβ1-1-ontoβπ |
9 | | f1ofo 6841 |
. . . . 5
β’ (( I
βΎ π):πβ1-1-ontoβπ β ( I βΎ π):πβontoβπ) |
10 | 8, 9 | mp1i 13 |
. . . 4
β’ (π½ β (TopOnβπ) β ( I βΎ π):πβontoβπ) |
11 | | elqtop3 23207 |
. . . 4
β’ ((π½ β (TopOnβπ) β§ ( I βΎ π):πβontoβπ) β (π₯ β (π½ qTop ( I βΎ π)) β (π₯ β π β§ (β‘( I βΎ π) β π₯) β π½))) |
12 | 10, 11 | mpdan 686 |
. . 3
β’ (π½ β (TopOnβπ) β (π₯ β (π½ qTop ( I βΎ π)) β (π₯ β π β§ (β‘( I βΎ π) β π₯) β π½))) |
13 | | toponss 22429 |
. . . . 5
β’ ((π½ β (TopOnβπ) β§ π₯ β π½) β π₯ β π) |
14 | 13 | ex 414 |
. . . 4
β’ (π½ β (TopOnβπ) β (π₯ β π½ β π₯ β π)) |
15 | 14 | pm4.71rd 564 |
. . 3
β’ (π½ β (TopOnβπ) β (π₯ β π½ β (π₯ β π β§ π₯ β π½))) |
16 | 7, 12, 15 | 3bitr4d 311 |
. 2
β’ (π½ β (TopOnβπ) β (π₯ β (π½ qTop ( I βΎ π)) β π₯ β π½)) |
17 | 16 | eqrdv 2731 |
1
β’ (π½ β (TopOnβπ) β (π½ qTop ( I βΎ π)) = π½) |