Theorem xpeq2 4619

Description: Equality theorem for cross product. (Contributed by NM, 5-Jul-1994.)

Assertion

Ref	Expression
xpeq2	⊢ (𝐴 = 𝐵 → (𝐶 × 𝐴) = (𝐶 × 𝐵))

Proof of Theorem xpeq2

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		eleq2 2230	. . . 4 ⊢ (𝐴 = 𝐵 → (𝑦 ∈ 𝐴 ↔ 𝑦 ∈ 𝐵))
2	1	anbi2d 460	. . 3 ⊢ (𝐴 = 𝐵 → ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐴) ↔ (𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐵)))
3	2	opabbidv 4048	. 2 ⊢ (𝐴 = 𝐵 → {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐴)} = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐵)})
4		df-xp 4610	. 2 ⊢ (𝐶 × 𝐴) = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐴)}
5		df-xp 4610	. 2 ⊢ (𝐶 × 𝐵) = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐵)}
6	3, 4, 5	3eqtr4g 2224	1 ⊢ (𝐴 = 𝐵 → (𝐶 × 𝐴) = (𝐶 × 𝐵))

Syntax hints:   → wi 4   ∧ wa 103   = wceq 1343   ∈ wcel 2136  {copab 4042   × cxp 4602

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-11 1494  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147

This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-opab 4044  df-xp 4610

This theorem is referenced by:  xpeq12  4623  xpeq2i  4625  xpeq2d  4628  xpeq0r  5026  xpdisj2  5029  pmvalg  6625  xpcomeng  6794  djueq12  7004  txuni2  12896  txbas  12898  txopn  12905  txrest  12916  txdis  12917  txdis1cn  12918  xmettxlem  13149  xmettx  13150