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Theorem xpeq1 4674
Description: Equality theorem for cross product. (Contributed by NM, 4-Jul-1994.)
Assertion
Ref Expression
xpeq1 (𝐴 = 𝐵 → (𝐴 × 𝐶) = (𝐵 × 𝐶))

Proof of Theorem xpeq1
Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eleq2 2257 . . . 4 (𝐴 = 𝐵 → (𝑥𝐴𝑥𝐵))
21anbi1d 465 . . 3 (𝐴 = 𝐵 → ((𝑥𝐴𝑦𝐶) ↔ (𝑥𝐵𝑦𝐶)))
32opabbidv 4096 . 2 (𝐴 = 𝐵 → {⟨𝑥, 𝑦⟩ ∣ (𝑥𝐴𝑦𝐶)} = {⟨𝑥, 𝑦⟩ ∣ (𝑥𝐵𝑦𝐶)})
4 df-xp 4666 . 2 (𝐴 × 𝐶) = {⟨𝑥, 𝑦⟩ ∣ (𝑥𝐴𝑦𝐶)}
5 df-xp 4666 . 2 (𝐵 × 𝐶) = {⟨𝑥, 𝑦⟩ ∣ (𝑥𝐵𝑦𝐶)}
63, 4, 53eqtr4g 2251 1 (𝐴 = 𝐵 → (𝐴 × 𝐶) = (𝐵 × 𝐶))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104   = wceq 1364  wcel 2164  {copab 4090   × cxp 4658
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-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-11 1517  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2175
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2180  df-cleq 2186  df-clel 2189  df-opab 4092  df-xp 4666
This theorem is referenced by:  xpeq12  4679  xpeq1i  4680  xpeq1d  4683  opthprc  4711  reseq2  4938  xpeq0r  5089  xpdisj1  5091  xpima1  5113  pmvalg  6715  xpsneng  6878  xpcomeng  6884  xpdom2g  6888  xpfi  6988  exmidomni  7203  exmidfodomrlemim  7263  hashxp  10900  txuni2  14435  txbas  14437  txopn  14444  txrest  14455  txdis  14456  txdis1cn  14457  xmettxlem  14688  xmettx  14689  dvmptid  14895
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