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Mirrors > Home > MPE Home > Th. List > ptopn2 | Structured version Visualization version GIF version |
Description: A sub-basic open set in the product topology. (Contributed by Stefan O'Rear, 22-Feb-2015.) |
Ref | Expression |
---|---|
ptopn2.a | β’ (π β π΄ β π) |
ptopn2.f | β’ (π β πΉ:π΄βΆTop) |
ptopn2.o | β’ (π β π β (πΉβπ)) |
Ref | Expression |
---|---|
ptopn2 | β’ (π β Xπ β π΄ if(π = π, π, βͺ (πΉβπ)) β (βtβπΉ)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ptopn2.a | . 2 β’ (π β π΄ β π) | |
2 | ptopn2.f | . 2 β’ (π β πΉ:π΄βΆTop) | |
3 | snfi 9048 | . . 3 β’ {π} β Fin | |
4 | 3 | a1i 11 | . 2 β’ (π β {π} β Fin) |
5 | ptopn2.o | . . . . . 6 β’ (π β π β (πΉβπ)) | |
6 | 5 | adantr 479 | . . . . 5 β’ ((π β§ π β π΄) β π β (πΉβπ)) |
7 | fveq2 6892 | . . . . . 6 β’ (π = π β (πΉβπ) = (πΉβπ)) | |
8 | 7 | eleq2d 2817 | . . . . 5 β’ (π = π β (π β (πΉβπ) β π β (πΉβπ))) |
9 | 6, 8 | syl5ibrcom 246 | . . . 4 β’ ((π β§ π β π΄) β (π = π β π β (πΉβπ))) |
10 | 9 | imp 405 | . . 3 β’ (((π β§ π β π΄) β§ π = π) β π β (πΉβπ)) |
11 | 2 | ffvelcdmda 7087 | . . . . 5 β’ ((π β§ π β π΄) β (πΉβπ) β Top) |
12 | eqid 2730 | . . . . . 6 β’ βͺ (πΉβπ) = βͺ (πΉβπ) | |
13 | 12 | topopn 22630 | . . . . 5 β’ ((πΉβπ) β Top β βͺ (πΉβπ) β (πΉβπ)) |
14 | 11, 13 | syl 17 | . . . 4 β’ ((π β§ π β π΄) β βͺ (πΉβπ) β (πΉβπ)) |
15 | 14 | adantr 479 | . . 3 β’ (((π β§ π β π΄) β§ Β¬ π = π) β βͺ (πΉβπ) β (πΉβπ)) |
16 | 10, 15 | ifclda 4564 | . 2 β’ ((π β§ π β π΄) β if(π = π, π, βͺ (πΉβπ)) β (πΉβπ)) |
17 | eldifn 4128 | . . . . 5 β’ (π β (π΄ β {π}) β Β¬ π β {π}) | |
18 | velsn 4645 | . . . . 5 β’ (π β {π} β π = π) | |
19 | 17, 18 | sylnib 327 | . . . 4 β’ (π β (π΄ β {π}) β Β¬ π = π) |
20 | 19 | iffalsed 4540 | . . 3 β’ (π β (π΄ β {π}) β if(π = π, π, βͺ (πΉβπ)) = βͺ (πΉβπ)) |
21 | 20 | adantl 480 | . 2 β’ ((π β§ π β (π΄ β {π})) β if(π = π, π, βͺ (πΉβπ)) = βͺ (πΉβπ)) |
22 | 1, 2, 4, 16, 21 | ptopn 23309 | 1 β’ (π β Xπ β π΄ if(π = π, π, βͺ (πΉβπ)) β (βtβπΉ)) |
Colors of variables: wff setvar class |
Syntax hints: Β¬ wn 3 β wi 4 β§ wa 394 = wceq 1539 β wcel 2104 β cdif 3946 ifcif 4529 {csn 4629 βͺ cuni 4909 βΆwf 6540 βcfv 6544 Xcixp 8895 Fincfn 8943 βtcpt 17390 Topctop 22617 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1795 ax-4 1809 ax-5 1911 ax-6 1969 ax-7 2009 ax-8 2106 ax-9 2114 ax-10 2135 ax-11 2152 ax-12 2169 ax-ext 2701 ax-rep 5286 ax-sep 5300 ax-nul 5307 ax-pow 5364 ax-pr 5428 ax-un 7729 |
This theorem depends on definitions: df-bi 206 df-an 395 df-or 844 df-3or 1086 df-3an 1087 df-tru 1542 df-fal 1552 df-ex 1780 df-nf 1784 df-sb 2066 df-mo 2532 df-eu 2561 df-clab 2708 df-cleq 2722 df-clel 2808 df-nfc 2883 df-ne 2939 df-ral 3060 df-rex 3069 df-reu 3375 df-rab 3431 df-v 3474 df-sbc 3779 df-csb 3895 df-dif 3952 df-un 3954 df-in 3956 df-ss 3966 df-pss 3968 df-nul 4324 df-if 4530 df-pw 4605 df-sn 4630 df-pr 4632 df-op 4636 df-uni 4910 df-int 4952 df-iun 5000 df-br 5150 df-opab 5212 df-mpt 5233 df-tr 5267 df-id 5575 df-eprel 5581 df-po 5589 df-so 5590 df-fr 5632 df-we 5634 df-xp 5683 df-rel 5684 df-cnv 5685 df-co 5686 df-dm 5687 df-rn 5688 df-res 5689 df-ima 5690 df-ord 6368 df-on 6369 df-lim 6370 df-suc 6371 df-iota 6496 df-fun 6546 df-fn 6547 df-f 6548 df-f1 6549 df-fo 6550 df-f1o 6551 df-fv 6552 df-om 7860 df-1o 8470 df-er 8707 df-ixp 8896 df-en 8944 df-fin 8947 df-fi 9410 df-topgen 17395 df-pt 17396 df-top 22618 df-bases 22671 |
This theorem is referenced by: ptcld 23339 |
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