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Theorem indval2 29850
Description: Alternate value of the indicator function generator. (Contributed by Thierry Arnoux, 2-Feb-2017.)
Assertion
Ref Expression
indval2 ((𝑂𝑉𝐴𝑂) → ((𝟭‘𝑂)‘𝐴) = ((𝐴 × {1}) ∪ ((𝑂𝐴) × {0})))

Proof of Theorem indval2
Dummy variable 𝑥 is distinct from all other variables.
StepHypRef Expression
1 dfmpt3 5973 . . . 4 (𝑥𝑂 ↦ if(𝑥𝐴, 1, 0)) = 𝑥𝑂 ({𝑥} × {if(𝑥𝐴, 1, 0)})
2 indval 29849 . . . 4 ((𝑂𝑉𝐴𝑂) → ((𝟭‘𝑂)‘𝐴) = (𝑥𝑂 ↦ if(𝑥𝐴, 1, 0)))
3 undif 4026 . . . . . . 7 (𝐴𝑂 ↔ (𝐴 ∪ (𝑂𝐴)) = 𝑂)
43biimpi 206 . . . . . 6 (𝐴𝑂 → (𝐴 ∪ (𝑂𝐴)) = 𝑂)
54adantl 482 . . . . 5 ((𝑂𝑉𝐴𝑂) → (𝐴 ∪ (𝑂𝐴)) = 𝑂)
65iuneq1d 4516 . . . 4 ((𝑂𝑉𝐴𝑂) → 𝑥 ∈ (𝐴 ∪ (𝑂𝐴))({𝑥} × {if(𝑥𝐴, 1, 0)}) = 𝑥𝑂 ({𝑥} × {if(𝑥𝐴, 1, 0)}))
71, 2, 63eqtr4a 2686 . . 3 ((𝑂𝑉𝐴𝑂) → ((𝟭‘𝑂)‘𝐴) = 𝑥 ∈ (𝐴 ∪ (𝑂𝐴))({𝑥} × {if(𝑥𝐴, 1, 0)}))
8 iunxun 4576 . . 3 𝑥 ∈ (𝐴 ∪ (𝑂𝐴))({𝑥} × {if(𝑥𝐴, 1, 0)}) = ( 𝑥𝐴 ({𝑥} × {if(𝑥𝐴, 1, 0)}) ∪ 𝑥 ∈ (𝑂𝐴)({𝑥} × {if(𝑥𝐴, 1, 0)}))
97, 8syl6eq 2676 . 2 ((𝑂𝑉𝐴𝑂) → ((𝟭‘𝑂)‘𝐴) = ( 𝑥𝐴 ({𝑥} × {if(𝑥𝐴, 1, 0)}) ∪ 𝑥 ∈ (𝑂𝐴)({𝑥} × {if(𝑥𝐴, 1, 0)})))
10 iftrue 4069 . . . . . . 7 (𝑥𝐴 → if(𝑥𝐴, 1, 0) = 1)
1110sneqd 4165 . . . . . 6 (𝑥𝐴 → {if(𝑥𝐴, 1, 0)} = {1})
1211xpeq2d 5104 . . . . 5 (𝑥𝐴 → ({𝑥} × {if(𝑥𝐴, 1, 0)}) = ({𝑥} × {1}))
1312iuneq2i 4510 . . . 4 𝑥𝐴 ({𝑥} × {if(𝑥𝐴, 1, 0)}) = 𝑥𝐴 ({𝑥} × {1})
14 iunxpconst 5141 . . . 4 𝑥𝐴 ({𝑥} × {1}) = (𝐴 × {1})
1513, 14eqtri 2648 . . 3 𝑥𝐴 ({𝑥} × {if(𝑥𝐴, 1, 0)}) = (𝐴 × {1})
16 eldifn 3716 . . . . . . 7 (𝑥 ∈ (𝑂𝐴) → ¬ 𝑥𝐴)
17 iffalse 4072 . . . . . . . 8 𝑥𝐴 → if(𝑥𝐴, 1, 0) = 0)
1817sneqd 4165 . . . . . . 7 𝑥𝐴 → {if(𝑥𝐴, 1, 0)} = {0})
1916, 18syl 17 . . . . . 6 (𝑥 ∈ (𝑂𝐴) → {if(𝑥𝐴, 1, 0)} = {0})
2019xpeq2d 5104 . . . . 5 (𝑥 ∈ (𝑂𝐴) → ({𝑥} × {if(𝑥𝐴, 1, 0)}) = ({𝑥} × {0}))
2120iuneq2i 4510 . . . 4 𝑥 ∈ (𝑂𝐴)({𝑥} × {if(𝑥𝐴, 1, 0)}) = 𝑥 ∈ (𝑂𝐴)({𝑥} × {0})
22 iunxpconst 5141 . . . 4 𝑥 ∈ (𝑂𝐴)({𝑥} × {0}) = ((𝑂𝐴) × {0})
2321, 22eqtri 2648 . . 3 𝑥 ∈ (𝑂𝐴)({𝑥} × {if(𝑥𝐴, 1, 0)}) = ((𝑂𝐴) × {0})
2415, 23uneq12i 3748 . 2 ( 𝑥𝐴 ({𝑥} × {if(𝑥𝐴, 1, 0)}) ∪ 𝑥 ∈ (𝑂𝐴)({𝑥} × {if(𝑥𝐴, 1, 0)})) = ((𝐴 × {1}) ∪ ((𝑂𝐴) × {0}))
259, 24syl6eq 2676 1 ((𝑂𝑉𝐴𝑂) → ((𝟭‘𝑂)‘𝐴) = ((𝐴 × {1}) ∪ ((𝑂𝐴) × {0})))
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wa 384   = wceq 1480  wcel 1992  cdif 3557  cun 3558  wss 3560  ifcif 4063  {csn 4153   ciun 4490  cmpt 4678   × cxp 5077  cfv 5850  0cc0 9881  1c1 9882  𝟭cind 29846
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1719  ax-4 1734  ax-5 1841  ax-6 1890  ax-7 1937  ax-9 2001  ax-10 2021  ax-11 2036  ax-12 2049  ax-13 2250  ax-ext 2606  ax-rep 4736  ax-sep 4746  ax-nul 4754  ax-pow 4808  ax-pr 4872
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1038  df-tru 1483  df-ex 1702  df-nf 1707  df-sb 1883  df-eu 2478  df-mo 2479  df-clab 2613  df-cleq 2619  df-clel 2622  df-nfc 2756  df-ne 2797  df-ral 2917  df-rex 2918  df-reu 2919  df-rab 2921  df-v 3193  df-sbc 3423  df-csb 3520  df-dif 3563  df-un 3565  df-in 3567  df-ss 3574  df-nul 3897  df-if 4064  df-pw 4137  df-sn 4154  df-pr 4156  df-op 4160  df-uni 4408  df-iun 4492  df-br 4619  df-opab 4679  df-mpt 4680  df-id 4994  df-xp 5085  df-rel 5086  df-cnv 5087  df-co 5088  df-dm 5089  df-rn 5090  df-res 5091  df-ima 5092  df-iota 5813  df-fun 5852  df-fn 5853  df-f 5854  df-f1 5855  df-fo 5856  df-f1o 5857  df-fv 5858  df-ind 29847
This theorem is referenced by: (None)
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