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Mirrors > Home > MPE Home > Th. List > xpfi | Structured version Visualization version GIF version |
Description: The Cartesian product of two finite sets is finite. (Contributed by Jeff Madsen, 2-Sep-2009.) (Revised by Mario Carneiro, 12-Mar-2015.) Avoid ax-pow 5370. (Revised by BTernaryTau, 10-Jan-2025.) |
Ref | Expression |
---|---|
xpfi | ⊢ ((𝐴 ∈ Fin ∧ 𝐵 ∈ Fin) → (𝐴 × 𝐵) ∈ Fin) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | unfi 9209 | . . 3 ⊢ ((𝐴 ∈ Fin ∧ 𝐵 ∈ Fin) → (𝐴 ∪ 𝐵) ∈ Fin) | |
2 | pwfi 9354 | . . . 4 ⊢ ((𝐴 ∪ 𝐵) ∈ Fin ↔ 𝒫 (𝐴 ∪ 𝐵) ∈ Fin) | |
3 | pwfi 9354 | . . . 4 ⊢ (𝒫 (𝐴 ∪ 𝐵) ∈ Fin ↔ 𝒫 𝒫 (𝐴 ∪ 𝐵) ∈ Fin) | |
4 | 2, 3 | bitri 275 | . . 3 ⊢ ((𝐴 ∪ 𝐵) ∈ Fin ↔ 𝒫 𝒫 (𝐴 ∪ 𝐵) ∈ Fin) |
5 | 1, 4 | sylib 218 | . 2 ⊢ ((𝐴 ∈ Fin ∧ 𝐵 ∈ Fin) → 𝒫 𝒫 (𝐴 ∪ 𝐵) ∈ Fin) |
6 | xpsspw 5821 | . 2 ⊢ (𝐴 × 𝐵) ⊆ 𝒫 𝒫 (𝐴 ∪ 𝐵) | |
7 | ssfi 9211 | . 2 ⊢ ((𝒫 𝒫 (𝐴 ∪ 𝐵) ∈ Fin ∧ (𝐴 × 𝐵) ⊆ 𝒫 𝒫 (𝐴 ∪ 𝐵)) → (𝐴 × 𝐵) ∈ Fin) | |
8 | 5, 6, 7 | sylancl 586 | 1 ⊢ ((𝐴 ∈ Fin ∧ 𝐵 ∈ Fin) → (𝐴 × 𝐵) ∈ Fin) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ∧ wa 395 ∈ wcel 2105 ∪ cun 3960 ⊆ wss 3962 𝒫 cpw 4604 × cxp 5686 Fincfn 8983 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1791 ax-4 1805 ax-5 1907 ax-6 1964 ax-7 2004 ax-8 2107 ax-9 2115 ax-10 2138 ax-11 2154 ax-12 2174 ax-ext 2705 ax-sep 5301 ax-nul 5311 ax-pr 5437 ax-un 7753 |
This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3or 1087 df-3an 1088 df-tru 1539 df-fal 1549 df-ex 1776 df-nf 1780 df-sb 2062 df-mo 2537 df-eu 2566 df-clab 2712 df-cleq 2726 df-clel 2813 df-nfc 2889 df-ne 2938 df-ral 3059 df-rex 3068 df-reu 3378 df-rab 3433 df-v 3479 df-sbc 3791 df-dif 3965 df-un 3967 df-in 3969 df-ss 3979 df-pss 3982 df-nul 4339 df-if 4531 df-pw 4606 df-sn 4631 df-pr 4633 df-op 4637 df-uni 4912 df-br 5148 df-opab 5210 df-mpt 5231 df-tr 5265 df-id 5582 df-eprel 5588 df-po 5596 df-so 5597 df-fr 5640 df-we 5642 df-xp 5694 df-rel 5695 df-cnv 5696 df-co 5697 df-dm 5698 df-rn 5699 df-res 5700 df-ima 5701 df-ord 6388 df-on 6389 df-lim 6390 df-suc 6391 df-iota 6515 df-fun 6564 df-fn 6565 df-f 6566 df-f1 6567 df-fo 6568 df-f1o 6569 df-fv 6570 df-om 7887 df-1o 8504 df-en 8984 df-dom 8985 df-fin 8987 |
This theorem is referenced by: 3xpfi 9357 fodomfir 9365 mapfi 9385 fsuppxpfi 9422 infxpenlem 10050 ficardadju 10237 ackbij1lem9 10264 ackbij1lem10 10265 hashxplem 14468 hashmap 14470 fsum2dlem 15802 fsumcom2 15806 ackbijnn 15860 fprod2dlem 16012 fprodcom2 16016 rexpen 16260 crth 16811 phimullem 16812 prmreclem3 16951 gsumcom3fi 20011 ablfaclem3 20121 gsumdixp 20332 frlmbas3 21813 gsumbagdiag 21968 psrass1lem 21969 evlslem2 22120 mamudm 22414 mamufacex 22415 mamures 22416 mamucl 22420 mamudi 22422 mamudir 22423 mamuvs1 22424 mamuvs2 22425 matsca2 22441 matbas2 22442 matplusg2 22448 matvsca2 22449 matplusgcell 22454 matsubgcell 22455 matvscacell 22457 matgsum 22458 mamumat1cl 22460 mattposcl 22474 mdetrsca 22624 mdetunilem9 22641 pmatcoe1fsupp 22722 tsmsxplem1 24176 tsmsxplem2 24177 tsmsxp 24178 i1fadd 25743 i1fmul 25744 itg1addlem4 25747 itg1addlem4OLD 25748 fsumdvdsmul 27252 fsumdvdsmulOLD 27254 fsumvma 27271 lgsquadlem1 27438 lgsquadlem2 27439 lgsquadlem3 27440 madefi 27964 relfi 32621 fsumiunle 32835 elrgspnlem2 33232 matdim 33642 fedgmullem1 33656 sibfof 34321 hgt750lemb 34649 erdszelem10 35184 matunitlindflem2 37603 matunitlindf 37604 poimirlem26 37632 poimirlem27 37633 poimirlem28 37634 cntotbnd 37782 aks6d1c2 42111 sticksstones22 42149 pellex 42822 mnringmulrcld 44223 fourierdlem42 46104 etransclem44 46233 etransclem45 46234 etransclem47 46236 |
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