Theorem op1std 6233

Description: Extract the first member of an ordered pair. (Contributed by Mario Carneiro, 31-Aug-2015.)

Hypotheses

Ref	Expression
op1st.1	⊢ 𝐴 ∈ V
op1st.2	⊢ 𝐵 ∈ V

Assertion

Ref	Expression
op1std	⊢ (𝐶 = ⟨𝐴, 𝐵⟩ → (1st ‘𝐶) = 𝐴)

Proof of Theorem op1std

Step	Hyp	Ref	Expression
1		fveq2 5575	. 2 ⊢ (𝐶 = ⟨𝐴, 𝐵⟩ → (1st ‘𝐶) = (1st ‘⟨𝐴, 𝐵⟩))
2		op1st.1	. . 3 ⊢ 𝐴 ∈ V
3		op1st.2	. . 3 ⊢ 𝐵 ∈ V
4	2, 3	op1st 6231	. 2 ⊢ (1st ‘⟨𝐴, 𝐵⟩) = 𝐴
5	1, 4	eqtrdi 2253	1 ⊢ (𝐶 = ⟨𝐴, 𝐵⟩ → (1st ‘𝐶) = 𝐴)

Syntax hints:   → wi 4   = wceq 1372   ∈ wcel 2175  Vcvv 2771  ⟨cop 3635  ‘cfv 5270  1^st c1st 6223

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 710  ax-5 1469  ax-7 1470  ax-gen 1471  ax-ie1 1515  ax-ie2 1516  ax-8 1526  ax-10 1527  ax-11 1528  ax-i12 1529  ax-bndl 1531  ax-4 1532  ax-17 1548  ax-i9 1552  ax-ial 1556  ax-i5r 1557  ax-13 2177  ax-14 2178  ax-ext 2186  ax-sep 4161  ax-pow 4217  ax-pr 4252  ax-un 4479

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1375  df-nf 1483  df-sb 1785  df-eu 2056  df-mo 2057  df-clab 2191  df-cleq 2197  df-clel 2200  df-nfc 2336  df-ral 2488  df-rex 2489  df-v 2773  df-sbc 2998  df-un 3169  df-in 3171  df-ss 3178  df-pw 3617  df-sn 3638  df-pr 3639  df-op 3641  df-uni 3850  df-br 4044  df-opab 4105  df-mpt 4106  df-id 4339  df-xp 4680  df-rel 4681  df-cnv 4682  df-co 4683  df-dm 4684  df-rn 4685  df-iota 5231  df-fun 5272  df-fv 5278  df-1st 6225

This theorem is referenced by:  xp1st  6250  sbcopeq1a  6272  csbopeq1a  6273  eloprabi  6281  mpomptsx  6282  dmmpossx  6284  fmpox  6285  fmpoco  6301  df1st2  6304  xporderlem  6316  xpf1o  6940  fisumcom2  11691  fprodcom2fi  11879  txbas  14672  cnmpt1st  14702  txhmeo  14733  lgsquadlem1  15496  lgsquadlem2  15497