Theorem fvmptg 5248

Description: Value of a function given in maps-to notation. (Contributed by NM, 2-Oct-2007.) (Revised by Mario Carneiro, 31-Aug-2015.)

Hypotheses

Ref	Expression
fvmptg.1	⊢ (𝑥 = 𝐴 → 𝐵 = 𝐶)
fvmptg.2	⊢ 𝐹 = (𝑥 ∈ 𝐷 ↦ 𝐵)

Assertion

Ref	Expression
fvmptg	⊢ ((𝐴 ∈ 𝐷 ∧ 𝐶 ∈ 𝑅) → (𝐹‘𝐴) = 𝐶)

Distinct variable groups:   𝑥,𝐴   𝑥,𝐶   𝑥,𝐷

Allowed substitution hints:   𝐵(𝑥)   𝑅(𝑥)   𝐹(𝑥)

Proof of Theorem fvmptg

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		eqid 2040	. 2 ⊢ 𝐶 = 𝐶
2		fvmptg.1	. . . 4 ⊢ (𝑥 = 𝐴 → 𝐵 = 𝐶)
3	2	eqeq2d 2051	. . 3 ⊢ (𝑥 = 𝐴 → (𝑦 = 𝐵 ↔ 𝑦 = 𝐶))
4		eqeq1 2046	. . 3 ⊢ (𝑦 = 𝐶 → (𝑦 = 𝐶 ↔ 𝐶 = 𝐶))
5		moeq 2716	. . . 4 ⊢ ∃*𝑦 𝑦 = 𝐵
6	5	a1i 9	. . 3 ⊢ (𝑥 ∈ 𝐷 → ∃*𝑦 𝑦 = 𝐵)
7		fvmptg.2	. . . 4 ⊢ 𝐹 = (𝑥 ∈ 𝐷 ↦ 𝐵)
8		df-mpt 3820	. . . 4 ⊢ (𝑥 ∈ 𝐷 ↦ 𝐵) = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ 𝐷 ∧ 𝑦 = 𝐵)}
9	7, 8	eqtri 2060	. . 3 ⊢ 𝐹 = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ 𝐷 ∧ 𝑦 = 𝐵)}
10	3, 4, 6, 9	fvopab3ig 5246	. 2 ⊢ ((𝐴 ∈ 𝐷 ∧ 𝐶 ∈ 𝑅) → (𝐶 = 𝐶 → (𝐹‘𝐴) = 𝐶))
11	1, 10	mpi 15	1 ⊢ ((𝐴 ∈ 𝐷 ∧ 𝐶 ∈ 𝑅) → (𝐹‘𝐴) = 𝐶)

Syntax hints:   → wi 4   ∧ wa 97   = wceq 1243   ∈ wcel 1393  ∃*wmo 1901  {copab 3817   ↦ cmpt 3818  ‘cfv 4902

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-14 1405  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022  ax-sep 3875  ax-pow 3927  ax-pr 3944

This theorem depends on definitions:  df-bi 110  df-3an 887  df-tru 1246  df-nf 1350  df-sb 1646  df-eu 1903  df-mo 1904  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-ral 2311  df-rex 2312  df-v 2559  df-sbc 2765  df-un 2922  df-in 2924  df-ss 2931  df-pw 3361  df-sn 3381  df-pr 3382  df-op 3384  df-uni 3581  df-br 3765  df-opab 3819  df-mpt 3820  df-id 4030  df-xp 4351  df-rel 4352  df-cnv 4353  df-co 4354  df-dm 4355  df-iota 4867  df-fun 4904  df-fv 4910

This theorem is referenced by:  fvmpt  5249  fvmpts  5250  fvmpt3  5251  fvmpt2  5254  f1mpt  5410  fnofval  5721  caofinvl  5733  1stvalg  5769  2ndvalg  5770  brtpos2  5866  frec0g  5983  frecsuclem3  5990  sucinc  6025  sucinc2  6026  omcl  6041  oeicl  6042  oav2  6043  omv2  6045  cardval3ex  6365  ceilqval  9148  monoord2  9236  iseqdistr  9249  serile  9253  cjval  9445  reval  9449  imval  9450  cvg1nlemcau  9583  cvg1nlemres  9584  absval  9599  resqrexlemglsq  9620  resqrexlemga  9621  climmpt  9821  climle  9854  climcvg1nlem  9868