Mathbox for Alexander van der Vekens < Previous   Next > Nearby theorems Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  dfatafv2rnb Structured version   Visualization version   GIF version

Theorem dfatafv2rnb 43770
 Description: The alternate function value at a class 𝐴 is defined, i.e. in the range of the function, iff the function is defined at 𝐴. (Contributed by AV, 2-Sep-2022.)
Assertion
Ref Expression
dfatafv2rnb (𝐹 defAt 𝐴 ↔ (𝐹''''𝐴) ∈ ran 𝐹)

Proof of Theorem dfatafv2rnb
StepHypRef Expression
1 funressndmafv2rn 43766 . 2 (𝐹 defAt 𝐴 → (𝐹''''𝐴) ∈ ran 𝐹)
2 ndfatafv2nrn 43764 . . . 4 𝐹 defAt 𝐴 → (𝐹''''𝐴) ∉ ran 𝐹)
3 df-nel 3095 . . . 4 ((𝐹''''𝐴) ∉ ran 𝐹 ↔ ¬ (𝐹''''𝐴) ∈ ran 𝐹)
42, 3sylib 221 . . 3 𝐹 defAt 𝐴 → ¬ (𝐹''''𝐴) ∈ ran 𝐹)
54con4i 114 . 2 ((𝐹''''𝐴) ∈ ran 𝐹𝐹 defAt 𝐴)
61, 5impbii 212 1 (𝐹 defAt 𝐴 ↔ (𝐹''''𝐴) ∈ ran 𝐹)
 Colors of variables: wff setvar class Syntax hints:  ¬ wn 3   ↔ wb 209   ∈ wcel 2112   ∉ wnel 3094  ran crn 5524   defAt wdfat 43659  ''''cafv2 43751 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2114  ax-9 2122  ax-10 2143  ax-11 2159  ax-12 2176  ax-ext 2773  ax-sep 5170  ax-nul 5177  ax-pr 5298  ax-un 7445 This theorem depends on definitions:  df-bi 210  df-an 400  df-or 845  df-3an 1086  df-tru 1541  df-ex 1782  df-nf 1786  df-sb 2070  df-mo 2601  df-eu 2632  df-clab 2780  df-cleq 2794  df-clel 2873  df-nfc 2941  df-nel 3095  df-ral 3114  df-rex 3115  df-rab 3118  df-v 3446  df-sbc 3724  df-dif 3887  df-un 3889  df-in 3891  df-ss 3901  df-nul 4247  df-if 4429  df-pw 4502  df-sn 4529  df-pr 4531  df-op 4535  df-uni 4804  df-br 5034  df-opab 5096  df-id 5428  df-xp 5529  df-rel 5530  df-cnv 5531  df-co 5532  df-dm 5533  df-rn 5534  df-res 5535  df-iota 6287  df-fun 6330  df-dfat 43662  df-afv2 43752 This theorem is referenced by:  dmafv2rnb  43772  afv2elrn  43774  tz6.12i-afv2  43786  afv2ndeffv0  43803  afv2rnfveq  43805
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