Theorem op1std 6372

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 5690	. 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 6370	. 2 ⊢ (1st ‘⟨𝐴, 𝐵⟩) = 𝐴
5	1, 4	eqtrdi 2287	1 ⊢ (𝐶 = ⟨𝐴, 𝐵⟩ → (1st ‘𝐶) = 𝐴)

Syntax hints:   → wi 4   = wceq 1402   ∈ wcel 2209  Vcvv 2821  ⟨cop 3708  ‘cfv 5372  1^st c1st 6362

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 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4244  ax-pow 4306  ax-pr 4341  ax-un 4573

This theorem depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-v 2823  df-sbc 3052  df-un 3224  df-in 3226  df-ss 3233  df-pw 3687  df-sn 3711  df-pr 3712  df-op 3714  df-uni 3931  df-br 4126  df-opab 4188  df-mpt 4189  df-id 4433  df-xp 4775  df-rel 4776  df-cnv 4777  df-co 4778  df-dm 4779  df-rn 4780  df-iota 5332  df-fun 5374  df-fv 5380  df-1st 6364

This theorem is referenced by:  xp1st  6389  sbcopeq1a  6411  csbopeq1a  6412  eloprabi  6422  mpomptsx  6423  dmmpossx  6425  fmpox  6426  fmpoco  6442  df1st2  6445  xporderlem  6457  xpf1o  7134  mapunen  7141  fisumcom2  12183  fprodcom2fi  12371  txbas  15282  cnmpt1st  15312  txhmeo  15343  lgsquadlem1  16110  lgsquadlem2  16111