nltpnft - Metamath Proof Explorer

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Theorem nltpnft 12719

Description: An extended real is not less than plus infinity iff they are equal. (Contributed by NM, 30-Jan-2006.)

**Assertion**
Ref	Expression
nltpnft	⊢ (𝐴 ∈ ℝ^* → (𝐴 = +∞ ↔ ¬ 𝐴 < +∞))

**Proof of Theorem nltpnft**
Step	Hyp	Ref	Expression
1		pnfxr 10852	. . . 4 ⊢ +∞ ∈ ℝ^*
2		xrltnr 12676	. . . 4 ⊢ (+∞ ∈ ℝ^* → ¬ +∞ < +∞)
3	1, 2	ax-mp 5	. . 3 ⊢ ¬ +∞ < +∞
4		breq1 5042	. . 3 ⊢ (𝐴 = +∞ → (𝐴 < +∞ ↔ +∞ < +∞))
5	3, 4	mtbiri 330	. 2 ⊢ (𝐴 = +∞ → ¬ 𝐴 < +∞)
6		pnfge 12687	. . . 4 ⊢ (𝐴 ∈ ℝ^* → 𝐴 ≤ +∞)
7		xrleloe 12699	. . . . 5 ⊢ ((𝐴 ∈ ℝ^* ∧ +∞ ∈ ℝ^*) → (𝐴 ≤ +∞ ↔ (𝐴 < +∞ ∨ 𝐴 = +∞)))
8	1, 7	mpan2 691	. . . 4 ⊢ (𝐴 ∈ ℝ^* → (𝐴 ≤ +∞ ↔ (𝐴 < +∞ ∨ 𝐴 = +∞)))
9	6, 8	mpbid 235	. . 3 ⊢ (𝐴 ∈ ℝ^* → (𝐴 < +∞ ∨ 𝐴 = +∞))
10	9	ord 864	. 2 ⊢ (𝐴 ∈ ℝ^* → (¬ 𝐴 < +∞ → 𝐴 = +∞))
11	5, 10	impbid2 229	1 ⊢ (𝐴 ∈ ℝ^* → (𝐴 = +∞ ↔ ¬ 𝐴 < +∞))

Colors of variables: wff setvar class

Syntax hints: ¬ wn 3 → wi 4 ↔ wb 209 ∨ wo 847 = wceq 1543 ∈ wcel 2112 class class class wbr 5039 +∞cpnf 10829 ℝ^*cxr 10831 < clt 10832 ≤ cle 10833

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1803 ax-4 1817 ax-5 1918 ax-6 1976 ax-7 2018 ax-8 2114 ax-9 2122 ax-10 2143 ax-11 2160 ax-12 2177 ax-ext 2708 ax-sep 5177 ax-nul 5184 ax-pow 5243 ax-pr 5307 ax-un 7501 ax-cnex 10750 ax-resscn 10751 ax-pre-lttri 10768 ax-pre-lttrn 10769

This theorem depends on definitions: df-bi 210 df-an 400 df-or 848 df-3or 1090 df-3an 1091 df-tru 1546 df-fal 1556 df-ex 1788 df-nf 1792 df-sb 2073 df-mo 2539 df-eu 2568 df-clab 2715 df-cleq 2728 df-clel 2809 df-nfc 2879 df-ne 2933 df-nel 3037 df-ral 3056 df-rex 3057 df-rab 3060 df-v 3400 df-sbc 3684 df-csb 3799 df-dif 3856 df-un 3858 df-in 3860 df-ss 3870 df-nul 4224 df-if 4426 df-pw 4501 df-sn 4528 df-pr 4530 df-op 4534 df-uni 4806 df-br 5040 df-opab 5102 df-mpt 5121 df-id 5440 df-po 5453 df-so 5454 df-xp 5542 df-rel 5543 df-cnv 5544 df-co 5545 df-dm 5546 df-rn 5547 df-res 5548 df-ima 5549 df-iota 6316 df-fun 6360 df-fn 6361 df-f 6362 df-f1 6363 df-fo 6364 df-f1o 6365 df-fv 6366 df-er 8369 df-en 8605 df-dom 8606 df-sdom 8607 df-pnf 10834 df-mnf 10835 df-xr 10836 df-ltxr 10837 df-le 10838

This theorem is referenced by: xgepnf 12720 xrrebnd 12723 xlt2add 12815 supxrbnd1 12876 supxrbnd2 12877 supxrgtmnf 12884 supxrre2 12886 ioopnfsup 13402 icopnfsup 13403 xrsdsreclblem 20363 ovoliun 24356 ovolicopnf 24375 voliunlem3 24403 volsup 24407 itg2seq 24594 nmoreltpnf 28804 nmopreltpnf 29904 ismblfin 35504 supxrgere 42486 supxrgelem 42490 supxrge 42491 suplesup 42492 nepnfltpnf 42495 xrpnf 42642 sge0repnf 43542 sge0rpcpnf 43577 sge0rernmpt 43578

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