dfioo2 - Metamath Proof Explorer

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Theorem dfioo2 13490

Description: Alternate definition of the set of open intervals of extended reals. (Contributed by NM, 1-Mar-2007.) (Revised by Mario Carneiro, 1-Sep-2015.)

**Assertion**
Ref	Expression
dfioo2	⊢ (,) = (𝑥 ∈ ℝ^, 𝑦 ∈ ℝ^ ↦ {𝑤 ∈ ℝ ∣ (𝑥 < 𝑤 ∧ 𝑤 < 𝑦)})

Distinct variable group: 𝑥,𝑤,𝑦

**Proof of Theorem dfioo2**
Step	Hyp	Ref	Expression
1		ioof 13487	. . . 4 ⊢ (,):(ℝ^* × ℝ^*)⟶𝒫 ℝ
2		ffn 6736	. . . 4 ⊢ ((,):(ℝ^* × ℝ^)⟶𝒫 ℝ → (,) Fn (ℝ^ × ℝ^*))
3	1, 2	ax-mp 5	. . 3 ⊢ (,) Fn (ℝ^* × ℝ^*)
4		fnov 7564	. . 3 ⊢ ((,) Fn (ℝ^* × ℝ^) ↔ (,) = (𝑥 ∈ ℝ^, 𝑦 ∈ ℝ^* ↦ (𝑥(,)𝑦)))
5	3, 4	mpbi 230	. 2 ⊢ (,) = (𝑥 ∈ ℝ^, 𝑦 ∈ ℝ^ ↦ (𝑥(,)𝑦))
6		iooval2 13420	. . 3 ⊢ ((𝑥 ∈ ℝ^* ∧ 𝑦 ∈ ℝ^*) → (𝑥(,)𝑦) = {𝑤 ∈ ℝ ∣ (𝑥 < 𝑤 ∧ 𝑤 < 𝑦)})
7	6	mpoeq3ia 7511	. 2 ⊢ (𝑥 ∈ ℝ^, 𝑦 ∈ ℝ^ ↦ (𝑥(,)𝑦)) = (𝑥 ∈ ℝ^, 𝑦 ∈ ℝ^ ↦ {𝑤 ∈ ℝ ∣ (𝑥 < 𝑤 ∧ 𝑤 < 𝑦)})
8	5, 7	eqtri 2765	1 ⊢ (,) = (𝑥 ∈ ℝ^, 𝑦 ∈ ℝ^ ↦ {𝑤 ∈ ℝ ∣ (𝑥 < 𝑤 ∧ 𝑤 < 𝑦)})

Colors of variables: wff setvar class

Syntax hints: ∧ wa 395 = wceq 1540 {crab 3436 𝒫 cpw 4600 class class class wbr 5143 × cxp 5683 Fn wfn 6556 ⟶wf 6557 (class class class)co 7431 ∈ cmpo 7433 ℝcr 11154 ℝ^*cxr 11294 < clt 11295 (,)cioo 13387

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1795 ax-4 1809 ax-5 1910 ax-6 1967 ax-7 2007 ax-8 2110 ax-9 2118 ax-10 2141 ax-11 2157 ax-12 2177 ax-ext 2708 ax-sep 5296 ax-nul 5306 ax-pow 5365 ax-pr 5432 ax-un 7755 ax-cnex 11211 ax-resscn 11212 ax-pre-lttri 11229 ax-pre-lttrn 11230

This theorem depends on definitions: df-bi 207 df-an 396 df-or 849 df-3or 1088 df-3an 1089 df-tru 1543 df-fal 1553 df-ex 1780 df-nf 1784 df-sb 2065 df-mo 2540 df-eu 2569 df-clab 2715 df-cleq 2729 df-clel 2816 df-nfc 2892 df-ne 2941 df-nel 3047 df-ral 3062 df-rex 3071 df-rab 3437 df-v 3482 df-sbc 3789 df-csb 3900 df-dif 3954 df-un 3956 df-in 3958 df-ss 3968 df-nul 4334 df-if 4526 df-pw 4602 df-sn 4627 df-pr 4629 df-op 4633 df-uni 4908 df-iun 4993 df-br 5144 df-opab 5206 df-mpt 5226 df-id 5578 df-po 5592 df-so 5593 df-xp 5691 df-rel 5692 df-cnv 5693 df-co 5694 df-dm 5695 df-rn 5696 df-res 5697 df-ima 5698 df-iota 6514 df-fun 6563 df-fn 6564 df-f 6565 df-f1 6566 df-fo 6567 df-f1o 6568 df-fv 6569 df-ov 7434 df-oprab 7435 df-mpo 7436 df-1st 8014 df-2nd 8015 df-er 8745 df-en 8986 df-dom 8987 df-sdom 8988 df-pnf 11297 df-mnf 11298 df-xr 11299 df-ltxr 11300 df-le 11301 df-ioo 13391

This theorem is referenced by: (None)

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