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Theorem fvelrnb 5542
Description: A member of a function's range is a value of the function. (Contributed by NM, 31-Oct-1995.)
Assertion
Ref Expression
fvelrnb (𝐹 Fn 𝐴 → (𝐵 ∈ ran 𝐹 ↔ ∃𝑥𝐴 (𝐹𝑥) = 𝐵))
Distinct variable groups:   𝑥,𝐴   𝑥,𝐵   𝑥,𝐹

Proof of Theorem fvelrnb
Dummy variable 𝑦 is distinct from all other variables.
StepHypRef Expression
1 df-rex 2454 . . . 4 (∃𝑥𝐴 (𝐹𝑥) = 𝐵 ↔ ∃𝑥(𝑥𝐴 ∧ (𝐹𝑥) = 𝐵))
2 19.41v 1895 . . . . 5 (∃𝑥((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴) ↔ (∃𝑥(𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴))
3 simpl 108 . . . . . . . . . 10 ((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) → 𝑥𝐴)
43anim1i 338 . . . . . . . . 9 (((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴) → (𝑥𝐴𝐹 Fn 𝐴))
54ancomd 265 . . . . . . . 8 (((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴) → (𝐹 Fn 𝐴𝑥𝐴))
6 funfvex 5511 . . . . . . . . 9 ((Fun 𝐹𝑥 ∈ dom 𝐹) → (𝐹𝑥) ∈ V)
76funfni 5296 . . . . . . . 8 ((𝐹 Fn 𝐴𝑥𝐴) → (𝐹𝑥) ∈ V)
85, 7syl 14 . . . . . . 7 (((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴) → (𝐹𝑥) ∈ V)
9 simpr 109 . . . . . . . . 9 ((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) → (𝐹𝑥) = 𝐵)
109eleq1d 2239 . . . . . . . 8 ((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) → ((𝐹𝑥) ∈ V ↔ 𝐵 ∈ V))
1110adantr 274 . . . . . . 7 (((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴) → ((𝐹𝑥) ∈ V ↔ 𝐵 ∈ V))
128, 11mpbid 146 . . . . . 6 (((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴) → 𝐵 ∈ V)
1312exlimiv 1591 . . . . 5 (∃𝑥((𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴) → 𝐵 ∈ V)
142, 13sylbir 134 . . . 4 ((∃𝑥(𝑥𝐴 ∧ (𝐹𝑥) = 𝐵) ∧ 𝐹 Fn 𝐴) → 𝐵 ∈ V)
151, 14sylanb 282 . . 3 ((∃𝑥𝐴 (𝐹𝑥) = 𝐵𝐹 Fn 𝐴) → 𝐵 ∈ V)
1615expcom 115 . 2 (𝐹 Fn 𝐴 → (∃𝑥𝐴 (𝐹𝑥) = 𝐵𝐵 ∈ V))
17 fnrnfv 5541 . . . 4 (𝐹 Fn 𝐴 → ran 𝐹 = {𝑦 ∣ ∃𝑥𝐴 𝑦 = (𝐹𝑥)})
1817eleq2d 2240 . . 3 (𝐹 Fn 𝐴 → (𝐵 ∈ ran 𝐹𝐵 ∈ {𝑦 ∣ ∃𝑥𝐴 𝑦 = (𝐹𝑥)}))
19 eqeq1 2177 . . . . . 6 (𝑦 = 𝐵 → (𝑦 = (𝐹𝑥) ↔ 𝐵 = (𝐹𝑥)))
20 eqcom 2172 . . . . . 6 (𝐵 = (𝐹𝑥) ↔ (𝐹𝑥) = 𝐵)
2119, 20bitrdi 195 . . . . 5 (𝑦 = 𝐵 → (𝑦 = (𝐹𝑥) ↔ (𝐹𝑥) = 𝐵))
2221rexbidv 2471 . . . 4 (𝑦 = 𝐵 → (∃𝑥𝐴 𝑦 = (𝐹𝑥) ↔ ∃𝑥𝐴 (𝐹𝑥) = 𝐵))
2322elab3g 2881 . . 3 ((∃𝑥𝐴 (𝐹𝑥) = 𝐵𝐵 ∈ V) → (𝐵 ∈ {𝑦 ∣ ∃𝑥𝐴 𝑦 = (𝐹𝑥)} ↔ ∃𝑥𝐴 (𝐹𝑥) = 𝐵))
2418, 23sylan9bbr 460 . 2 (((∃𝑥𝐴 (𝐹𝑥) = 𝐵𝐵 ∈ V) ∧ 𝐹 Fn 𝐴) → (𝐵 ∈ ran 𝐹 ↔ ∃𝑥𝐴 (𝐹𝑥) = 𝐵))
2516, 24mpancom 420 1 (𝐹 Fn 𝐴 → (𝐵 ∈ ran 𝐹 ↔ ∃𝑥𝐴 (𝐹𝑥) = 𝐵))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 103  wb 104   = wceq 1348  wex 1485  wcel 2141  {cab 2156  wrex 2449  Vcvv 2730  ran crn 4610   Fn wfn 5191  cfv 5196
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-14 2144  ax-ext 2152  ax-sep 4105  ax-pow 4158  ax-pr 4192
This theorem depends on definitions:  df-bi 116  df-3an 975  df-tru 1351  df-nf 1454  df-sb 1756  df-eu 2022  df-mo 2023  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-ral 2453  df-rex 2454  df-v 2732  df-sbc 2956  df-un 3125  df-in 3127  df-ss 3134  df-pw 3566  df-sn 3587  df-pr 3588  df-op 3590  df-uni 3795  df-br 3988  df-opab 4049  df-mpt 4050  df-id 4276  df-xp 4615  df-rel 4616  df-cnv 4617  df-co 4618  df-dm 4619  df-rn 4620  df-iota 5158  df-fun 5198  df-fn 5199  df-fv 5204
This theorem is referenced by:  chfnrn  5605  rexrn  5631  ralrn  5632  elrnrexdmb  5634  ffnfv  5652  fconstfvm  5712  elunirn  5743  isoini  5795  canth  5805  reldm  6163  ordiso2  7009  eldju  7042  ctssdc  7087  uzn0  9491  frec2uzrand  10350  frecuzrdgtcl  10357  frecuzrdgfunlem  10364  uzin2  10940  reeff1o  13449
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