Theorem op1std 6215

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 5561	. 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 6213	. 2 ⊢ (1st ‘⟨𝐴, 𝐵⟩) = 𝐴
5	1, 4	eqtrdi 2245	1 ⊢ (𝐶 = ⟨𝐴, 𝐵⟩ → (1st ‘𝐶) = 𝐴)

Syntax hints:   → wi 4   = wceq 1364   ∈ wcel 2167  Vcvv 2763  ⟨cop 3626  ‘cfv 5259  1^st c1st 6205

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 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-13 2169  ax-14 2170  ax-ext 2178  ax-sep 4152  ax-pow 4208  ax-pr 4243  ax-un 4469

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1475  df-sb 1777  df-eu 2048  df-mo 2049  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-ral 2480  df-rex 2481  df-v 2765  df-sbc 2990  df-un 3161  df-in 3163  df-ss 3170  df-pw 3608  df-sn 3629  df-pr 3630  df-op 3632  df-uni 3841  df-br 4035  df-opab 4096  df-mpt 4097  df-id 4329  df-xp 4670  df-rel 4671  df-cnv 4672  df-co 4673  df-dm 4674  df-rn 4675  df-iota 5220  df-fun 5261  df-fv 5267  df-1st 6207

This theorem is referenced by:  xp1st  6232  sbcopeq1a  6254  csbopeq1a  6255  eloprabi  6263  mpomptsx  6264  dmmpossx  6266  fmpox  6267  fmpoco  6283  df1st2  6286  xporderlem  6298  xpf1o  6914  fisumcom2  11620  fprodcom2fi  11808  txbas  14578  cnmpt1st  14608  txhmeo  14639  lgsquadlem1  15402  lgsquadlem2  15403