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Theorem xpeq1 4739
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 2295 . . . 4 (𝐴 = 𝐵 → (𝑥𝐴𝑥𝐵))
21anbi1d 465 . . 3 (𝐴 = 𝐵 → ((𝑥𝐴𝑦𝐶) ↔ (𝑥𝐵𝑦𝐶)))
32opabbidv 4155 . 2 (𝐴 = 𝐵 → {⟨𝑥, 𝑦⟩ ∣ (𝑥𝐴𝑦𝐶)} = {⟨𝑥, 𝑦⟩ ∣ (𝑥𝐵𝑦𝐶)})
4 df-xp 4731 . 2 (𝐴 × 𝐶) = {⟨𝑥, 𝑦⟩ ∣ (𝑥𝐴𝑦𝐶)}
5 df-xp 4731 . 2 (𝐵 × 𝐶) = {⟨𝑥, 𝑦⟩ ∣ (𝑥𝐵𝑦𝐶)}
63, 4, 53eqtr4g 2289 1 (𝐴 = 𝐵 → (𝐴 × 𝐶) = (𝐵 × 𝐶))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104   = wceq 1397  wcel 2202  {copab 4149   × cxp 4723
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 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-11 1554  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-ext 2213
This theorem depends on definitions:  df-bi 117  df-tru 1400  df-nf 1509  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-opab 4151  df-xp 4731
This theorem is referenced by:  xpeq12  4744  xpeq1i  4745  xpeq1d  4748  opthprc  4777  reseq2  5008  xpeq0r  5159  xpdisj1  5161  xpima1  5183  pmvalg  6828  xpsneng  7006  xpcomeng  7012  xpdom2g  7016  xpfi  7124  exmidomni  7341  exmidfodomrlemim  7412  hashxp  11091  txuni2  14986  txbas  14988  txopn  14995  txrest  15006  txdis  15007  txdis1cn  15008  xmettxlem  15239  xmettx  15240  dvmptid  15446  incistruhgr  15947
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