xpexr2 - Metamath Proof Explorer

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Theorem xpexr2 7855

Description: If a nonempty Cartesian product is a set, so are both of its components. (Contributed by NM, 27-Aug-2006.)

**Assertion**
Ref	Expression
xpexr2	⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ (𝐴 × 𝐵) ≠ ∅) → (𝐴 ∈ V ∧ 𝐵 ∈ V))

**Proof of Theorem xpexr2**
Step	Hyp	Ref	Expression
1		xpnz 6111	. 2 ⊢ ((𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅) ↔ (𝐴 × 𝐵) ≠ ∅)
2		dmxp 5873	. . . . . 6 ⊢ (𝐵 ≠ ∅ → dom (𝐴 × 𝐵) = 𝐴)
3	2	adantl 481	. . . . 5 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ 𝐵 ≠ ∅) → dom (𝐴 × 𝐵) = 𝐴)
4		dmexg 7837	. . . . . 6 ⊢ ((𝐴 × 𝐵) ∈ 𝐶 → dom (𝐴 × 𝐵) ∈ V)
5	4	adantr 480	. . . . 5 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ 𝐵 ≠ ∅) → dom (𝐴 × 𝐵) ∈ V)
6	3, 5	eqeltrrd 2834	. . . 4 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ 𝐵 ≠ ∅) → 𝐴 ∈ V)
7		rnxp 6122	. . . . . 6 ⊢ (𝐴 ≠ ∅ → ran (𝐴 × 𝐵) = 𝐵)
8	7	adantl 481	. . . . 5 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ 𝐴 ≠ ∅) → ran (𝐴 × 𝐵) = 𝐵)
9		rnexg 7838	. . . . . 6 ⊢ ((𝐴 × 𝐵) ∈ 𝐶 → ran (𝐴 × 𝐵) ∈ V)
10	9	adantr 480	. . . . 5 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ 𝐴 ≠ ∅) → ran (𝐴 × 𝐵) ∈ V)
11	8, 10	eqeltrrd 2834	. . . 4 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ 𝐴 ≠ ∅) → 𝐵 ∈ V)
12	6, 11	anim12dan 619	. . 3 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ (𝐵 ≠ ∅ ∧ 𝐴 ≠ ∅)) → (𝐴 ∈ V ∧ 𝐵 ∈ V))
13	12	ancom2s 650	. 2 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → (𝐴 ∈ V ∧ 𝐵 ∈ V))
14	1, 13	sylan2br 595	1 ⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ (𝐴 × 𝐵) ≠ ∅) → (𝐴 ∈ V ∧ 𝐵 ∈ V))

Colors of variables: wff setvar class

Syntax hints: → wi 4 ∧ wa 395 = wceq 1541 ∈ wcel 2113 ≠ wne 2929 Vcvv 3437 ∅c0 4282 × cxp 5617 dom cdm 5619 ran crn 5620

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1796 ax-4 1810 ax-5 1911 ax-6 1968 ax-7 2009 ax-8 2115 ax-9 2123 ax-11 2162 ax-ext 2705 ax-sep 5236 ax-nul 5246 ax-pr 5372 ax-un 7674

This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3an 1088 df-tru 1544 df-fal 1554 df-ex 1781 df-sb 2068 df-clab 2712 df-cleq 2725 df-clel 2808 df-ne 2930 df-ral 3049 df-rex 3058 df-rab 3397 df-v 3439 df-dif 3901 df-un 3903 df-in 3905 df-ss 3915 df-nul 4283 df-if 4475 df-sn 4576 df-pr 4578 df-op 4582 df-uni 4859 df-br 5094 df-opab 5156 df-xp 5625 df-rel 5626 df-cnv 5627 df-dm 5629 df-rn 5630

This theorem is referenced by: xpfir 9159 bj-xpnzex 37024