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Theorem fressnfv 2898
Description: The value of a function restricted to a singleton.
Assertion
Ref Expression
fressnfv |- ((F Fn A /\ B e. A) -> ((F |` {B}):{B}-->C <-> (F` B) e. C))

Proof of Theorem fressnfv
StepHypRef Expression
1 sneq 1816 . . . . . . 7 |- (x = B -> {x} = {B})
2 reseq2 2576 . . . . . . . . 9 |- ({x} = {B} -> (F |` {x}) = (F |` {B}))
3 feq1 2748 . . . . . . . . 9 |- ((F |` {x}) = (F |` {B}) -> ((F |` {x}):{x}-->C <-> (F |` {B}):{x}-->C))
42, 3syl 12 . . . . . . . 8 |- ({x} = {B} -> ((F |` {x}):{x}-->C <-> (F |` {B}):{x}-->C))
5 feq2 2749 . . . . . . . 8 |- ({x} = {B} -> ((F |` {B}):{x}-->C <-> (F |` {B}):{B}-->C))
64, 5bitrd 406 . . . . . . 7 |- ({x} = {B} -> ((F |` {x}):{x}-->C <-> (F |` {B}):{B}-->C))
71, 6syl 12 . . . . . 6 |- (x = B -> ((F |` {x}):{x}-->C <-> (F |` {B}):{B}-->C))
8 fveq2 2832 . . . . . . 7 |- (x = B -> (F` x) = (F` B))
98eleq1d 1155 . . . . . 6 |- (x = B -> ((F` x) e. C <-> (F` B) e. C))
107, 9bibi12d 477 . . . . 5 |- (x = B -> (((F |` {x}):{x}-->C <-> (F` x) e. C) <-> ((F |` {B}):{B}-->C <-> (F` B) e. C)))
1110imbi2d 464 . . . 4 |- (x = B -> ((F Fn A -> ((F |` {x}):{x}-->C <-> (F` x) e. C)) <-> (F Fn A -> ((F |` {B}):{B}-->C <-> (F` B) e. C))))
12 fnressn 2897 . . . . . . 7 |- ((F Fn A /\ x e. A) -> (F |` {x}) = {<.x, (F` x)>.})
13 visset 1350 . . . . . . . . . . . . 13 |- x e. V
1413snid 1830 . . . . . . . . . . . 12 |- x e. {x}
15 fvres 2840 . . . . . . . . . . . 12 |- (x e. {x} -> ((F |` {x})` x) = (F` x))
1614, 15ax-mp 6 . . . . . . . . . . 11 |- ((F |` {x})` x) = (F` x)
17 opeq2 1877 . . . . . . . . . . 11 |- (((F |` {x})` x) = (F` x) -> <.x, ((F |` {x})` x)>. = <.x, (F` x)>.)
1816, 17ax-mp 6 . . . . . . . . . 10 |- <.x, ((F |` {x})` x)>. = <.x, (F` x)>.
1918sneqi 1817 . . . . . . . . 9 |- {<.x, ((F |` {x})` x)>.} = {<.x, (F` x)>.}
2019cleq2i 1111 . . . . . . . 8 |- ((F |` {x}) = {<.x, ((F |` {x})` x)>.} <-> (F |` {x}) = {<.x, (F` x)>.})
21 iba 486 . . . . . . . . . 10 |- ((F |` {x}) = {<.x, ((F |` {x})` x)>.} -> (((F |` {x})` x) e. C <-> (((F |` {x})` x) e. C /\ (F |` {x}) = {<.x, ((F |` {x})` x)>.})))
2216eleq1i 1152 . . . . . . . . . 10 |- (((F |` {x})` x) e. C <-> (F` x) e. C)
2321, 22syl5rbbr 413 . . . . . . . . 9 |- ((F |` {x}) = {<.x, ((F |` {x})` x)>.} -> ((((F |` {x})` x) e. C /\ (F |` {x}) = {<.x, ((F |` {x})` x)>.}) <-> (F` x) e. C))
2413fsn2 2896 . . . . . . . . 9 |- ((F |` {x}):{x}-->C <-> (((F |` {x})` x) e. C /\ (F |` {x}) = {<.x, ((F |` {x})` x)>.}))
2523, 24syl5bb 410 . . . . . . . 8 |- ((F |` {x}) = {<.x, ((F |` {x})` x)>.} -> ((F |` {x}):{x}-->C <-> (F` x) e. C))
2620, 25sylbir 176 . . . . . . 7 |- ((F |` {x}) = {<.x, (F` x)>.} -> ((F |` {x}):{x}-->C <-> (F` x) e. C))
2712, 26syl 12 . . . . . 6 |- ((F Fn A /\ x e. A) -> ((F |` {x}):{x}-->C <-> (F` x) e. C))
2827ancoms 334 . . . . 5 |- ((x e. A /\ F Fn A) -> ((F |` {x}):{x}-->C <-> (F` x) e. C))
2928exp 291 . . . 4 |- (x e. A -> (F Fn A -> ((F |` {x}):{x}-->C <-> (F` x) e. C)))
3011, 29vtoclga 1387 . . 3 |- (B e. A -> (F Fn A -> ((F |` {B}):{B}-->C <-> (F` B) e. C)))
3130imp 277 . 2 |- ((B e. A /\ F Fn A) -> ((F |` {B}):{B}-->C <-> (F` B) e. C))
3231ancoms 334 1 |- ((F Fn A /\ B e. A) -> ((F |` {B}):{B}-->C <-> (F` B) e. C))
Colors of variables: wff set class
Syntax hints:   -> wi 2   <-> wb 127   /\ wa 196   = wceq 1091   e. wcel 1092  {csn 1808  <.cop 1810   |` cres 2412   Fn wfn 2417  -->wf 2418  ` cfv 2422
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-7 676  ax-gen 677  ax-8 798  ax-9 799  ax-10 800  ax-11 801  ax-12 802  ax-13 804  ax-14 805  ax-16 922  ax-17 925  ax-ext 1074  ax-rep 1075  ax-un 1076  ax-pow 1077
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-3an 583  df-ex 679  df-sb 853  df-eu 1009  df-mo 1010  df-clab 1093  df-cleq 1097  df-clel 1099  df-rex 1206  df-reu 1207  df-v 1349  df-dif 1489  df-un 1490  df-in 1491  df-ss 1492  df-nul 1708  df-pw 1799  df-sn 1811  df-pr 1812  df-op 1815  df-uni 1920  df-br 2063  df-opab 2098  df-id 2125  df-xp 2424  df-rel 2425  df-cnv 2426  df-co 2427  df-dm 2428  df-rn 2429  df-res 2430  df-ima 2431  df-fun 2432  df-fn 2433  df-f 2434  df-f1 2435  df-fo 2436  df-f1o 2437  df-fv 2438
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