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Theorem fconst4 5458
 Description: Two ways to express a constant function. (Contributed by set.mm contributors, 8-Mar-2007.)
Assertion
Ref Expression
fconst4 (F:A–→{B} ↔ (F Fn A (F “ {B}) = A))

Proof of Theorem fconst4
StepHypRef Expression
1 fconst3 5457 . 2 (F:A–→{B} ↔ (F Fn A A (F “ {B})))
2 cnvimass 5016 . . . . . 6 (F “ {B}) dom F
3 fndm 5182 . . . . . 6 (F Fn A → dom F = A)
42, 3syl5sseq 3319 . . . . 5 (F Fn A → (F “ {B}) A)
54biantrurd 494 . . . 4 (F Fn A → (A (F “ {B}) ↔ ((F “ {B}) A A (F “ {B}))))
6 eqss 3287 . . . 4 ((F “ {B}) = A ↔ ((F “ {B}) A A (F “ {B})))
75, 6syl6bbr 254 . . 3 (F Fn A → (A (F “ {B}) ↔ (F “ {B}) = A))
87pm5.32i 618 . 2 ((F Fn A A (F “ {B})) ↔ (F Fn A (F “ {B}) = A))
91, 8bitri 240 1 (F:A–→{B} ↔ (F Fn A (F “ {B}) = A))
 Colors of variables: wff setvar class Syntax hints:   ↔ wb 176   ∧ wa 358   = wceq 1642   ⊆ wss 3257  {csn 3737   “ cima 4722  ◡ccnv 4771  dom cdm 4772   Fn wfn 4776  –→wf 4777 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-13 1712  ax-14 1714  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334  ax-nin 4078  ax-xp 4079  ax-cnv 4080  ax-1c 4081  ax-sset 4082  ax-si 4083  ax-ins2 4084  ax-ins3 4085  ax-typlower 4086  ax-sn 4087 This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-3or 935  df-3an 936  df-nan 1288  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-eu 2208  df-mo 2209  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2478  df-ne 2518  df-ral 2619  df-rex 2620  df-reu 2621  df-rmo 2622  df-rab 2623  df-v 2861  df-sbc 3047  df-nin 3211  df-compl 3212  df-in 3213  df-un 3214  df-dif 3215  df-symdif 3216  df-ss 3259  df-pss 3261  df-nul 3551  df-if 3663  df-pw 3724  df-sn 3741  df-pr 3742  df-uni 3892  df-int 3927  df-opk 4058  df-1c 4136  df-pw1 4137  df-uni1 4138  df-xpk 4185  df-cnvk 4186  df-ins2k 4187  df-ins3k 4188  df-imak 4189  df-cok 4190  df-p6 4191  df-sik 4192  df-ssetk 4193  df-imagek 4194  df-idk 4195  df-iota 4339  df-0c 4377  df-addc 4378  df-nnc 4379  df-fin 4380  df-lefin 4440  df-ltfin 4441  df-ncfin 4442  df-tfin 4443  df-evenfin 4444  df-oddfin 4445  df-sfin 4446  df-spfin 4447  df-phi 4565  df-op 4566  df-proj1 4567  df-proj2 4568  df-opab 4623  df-br 4640  df-co 4726  df-ima 4727  df-id 4767  df-xp 4784  df-cnv 4785  df-rn 4786  df-dm 4787  df-res 4788  df-fun 4789  df-fn 4790  df-f 4791  df-fo 4793  df-fv 4795 This theorem is referenced by: (None)
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