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Theorem txtop 21750
Description: The product of two topologies is a topology. (Contributed by Jeff Madsen, 2-Sep-2009.)
Assertion
Ref Expression
txtop ((𝑅 ∈ Top ∧ 𝑆 ∈ Top) → (𝑅 ×t 𝑆) ∈ Top)

Proof of Theorem txtop
Dummy variables 𝑢 𝑣 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eqid 2825 . . 3 ran (𝑢𝑅, 𝑣𝑆 ↦ (𝑢 × 𝑣)) = ran (𝑢𝑅, 𝑣𝑆 ↦ (𝑢 × 𝑣))
21txval 21745 . 2 ((𝑅 ∈ Top ∧ 𝑆 ∈ Top) → (𝑅 ×t 𝑆) = (topGen‘ran (𝑢𝑅, 𝑣𝑆 ↦ (𝑢 × 𝑣))))
3 topbas 21154 . . . 4 (𝑅 ∈ Top → 𝑅 ∈ TopBases)
4 topbas 21154 . . . 4 (𝑆 ∈ Top → 𝑆 ∈ TopBases)
51txbas 21748 . . . 4 ((𝑅 ∈ TopBases ∧ 𝑆 ∈ TopBases) → ran (𝑢𝑅, 𝑣𝑆 ↦ (𝑢 × 𝑣)) ∈ TopBases)
63, 4, 5syl2an 589 . . 3 ((𝑅 ∈ Top ∧ 𝑆 ∈ Top) → ran (𝑢𝑅, 𝑣𝑆 ↦ (𝑢 × 𝑣)) ∈ TopBases)
7 tgcl 21151 . . 3 (ran (𝑢𝑅, 𝑣𝑆 ↦ (𝑢 × 𝑣)) ∈ TopBases → (topGen‘ran (𝑢𝑅, 𝑣𝑆 ↦ (𝑢 × 𝑣))) ∈ Top)
86, 7syl 17 . 2 ((𝑅 ∈ Top ∧ 𝑆 ∈ Top) → (topGen‘ran (𝑢𝑅, 𝑣𝑆 ↦ (𝑢 × 𝑣))) ∈ Top)
92, 8eqeltrd 2906 1 ((𝑅 ∈ Top ∧ 𝑆 ∈ Top) → (𝑅 ×t 𝑆) ∈ Top)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 386  wcel 2164   × cxp 5344  ran crn 5347  cfv 6127  (class class class)co 6910  cmpt2 6912  topGenctg 16458  Topctop 21075  TopBasesctb 21127   ×t ctx 21741
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1894  ax-4 1908  ax-5 2009  ax-6 2075  ax-7 2112  ax-8 2166  ax-9 2173  ax-10 2192  ax-11 2207  ax-12 2220  ax-13 2389  ax-ext 2803  ax-sep 5007  ax-nul 5015  ax-pow 5067  ax-pr 5129  ax-un 7214
This theorem depends on definitions:  df-bi 199  df-an 387  df-or 879  df-3an 1113  df-tru 1660  df-ex 1879  df-nf 1883  df-sb 2068  df-mo 2605  df-eu 2640  df-clab 2812  df-cleq 2818  df-clel 2821  df-nfc 2958  df-ne 3000  df-ral 3122  df-rex 3123  df-rab 3126  df-v 3416  df-sbc 3663  df-csb 3758  df-dif 3801  df-un 3803  df-in 3805  df-ss 3812  df-nul 4147  df-if 4309  df-pw 4382  df-sn 4400  df-pr 4402  df-op 4406  df-uni 4661  df-iun 4744  df-br 4876  df-opab 4938  df-mpt 4955  df-id 5252  df-xp 5352  df-rel 5353  df-cnv 5354  df-co 5355  df-dm 5356  df-rn 5357  df-res 5358  df-ima 5359  df-iota 6090  df-fun 6129  df-fn 6130  df-f 6131  df-fv 6135  df-ov 6913  df-oprab 6914  df-mpt2 6915  df-1st 7433  df-2nd 7434  df-topgen 16464  df-top 21076  df-bases 21128  df-tx 21743
This theorem is referenced by:  txtopi  21771  txtopon  21772  txcld  21784  neitx  21788  txlly  21817  txnlly  21818  txcmplem1  21822  txcmp  21824  hausdiag  21826  txhaus  21828  tx1stc  21831  txkgen  21833  xkococn  21841  xkoinjcn  21868  txconn  21870  imasnopn  21871  imasncls  21873  utop2nei  22431  utop3cls  22432  qtophaus  30444  txpconn  31756
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