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Theorem intimasn2 44102
Description: Two ways to express the image of a singleton when the relation is an intersection. (Contributed by RP, 13-Apr-2020.)
Assertion
Ref Expression
intimasn2 (𝐵𝑉 → ( 𝐴 “ {𝐵}) = 𝑥𝐴 (𝑥 “ {𝐵}))
Distinct variable groups:   𝑥,𝐴   𝑥,𝐵
Allowed substitution hint:   𝑉(𝑥)

Proof of Theorem intimasn2
Dummy variable 𝑦 is distinct from all other variables.
StepHypRef Expression
1 intimasn 44101 . 2 (𝐵𝑉 → ( 𝐴 “ {𝐵}) = {𝑦 ∣ ∃𝑥𝐴 𝑦 = (𝑥 “ {𝐵})})
2 intima0 44092 . 2 𝑥𝐴 (𝑥 “ {𝐵}) = {𝑦 ∣ ∃𝑥𝐴 𝑦 = (𝑥 “ {𝐵})}
31, 2eqtr4di 2792 1 (𝐵𝑉 → ( 𝐴 “ {𝐵}) = 𝑥𝐴 (𝑥 “ {𝐵}))
Colors of variables: wff setvar class
Syntax hints:  wi 4   = wceq 1547  wcel 2119  {cab 2717  wrex 3063  {csn 4555   cint 4877   ciin 4922  cima 5621
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1802  ax-4 1816  ax-5 1917  ax-6 1974  ax-7 2015  ax-8 2121  ax-9 2129  ax-10 2152  ax-11 2168  ax-12 2189  ax-ext 2711  ax-sep 5218  ax-pr 5362  ax-un 7678
This theorem depends on definitions:  df-bi 208  df-an 397  df-or 854  df-3an 1094  df-tru 1550  df-fal 1560  df-ex 1787  df-nf 1791  df-sb 2074  df-clab 2718  df-cleq 2731  df-clel 2814  df-nfc 2888  df-ral 3054  df-rex 3064  df-rab 3392  df-v 3433  df-sbc 3724  df-dif 3886  df-un 3888  df-in 3890  df-ss 3900  df-nul 4262  df-if 4455  df-sn 4556  df-pr 4558  df-op 4562  df-uni 4839  df-int 4878  df-iin 4924  df-br 5073  df-opab 5135  df-xp 5624  df-cnv 5626  df-dm 5628  df-rn 5629  df-res 5630  df-ima 5631
This theorem is referenced by: (None)
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