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Mirrors > Home > MPE Home > Th. List > xaddnemnf | Structured version Visualization version GIF version |
Description: Closure of extended real addition in the subset ℝ* / {-∞}. (Contributed by Mario Carneiro, 20-Aug-2015.) |
Ref | Expression |
---|---|
xaddnemnf | ⊢ (((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | xrnemnf 13102 | . 2 ⊢ ((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) ↔ (𝐴 ∈ ℝ ∨ 𝐴 = +∞)) | |
2 | xrnemnf 13102 | . . . 4 ⊢ ((𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞) ↔ (𝐵 ∈ ℝ ∨ 𝐵 = +∞)) | |
3 | rexadd 13216 | . . . . . . 7 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 +𝑒 𝐵) = (𝐴 + 𝐵)) | |
4 | readdcl 11196 | . . . . . . 7 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 + 𝐵) ∈ ℝ) | |
5 | 3, 4 | eqeltrd 2832 | . . . . . 6 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 +𝑒 𝐵) ∈ ℝ) |
6 | 5 | renemnfd 11271 | . . . . 5 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 +𝑒 𝐵) ≠ -∞) |
7 | oveq2 7420 | . . . . . . 7 ⊢ (𝐵 = +∞ → (𝐴 +𝑒 𝐵) = (𝐴 +𝑒 +∞)) | |
8 | rexr 11265 | . . . . . . . 8 ⊢ (𝐴 ∈ ℝ → 𝐴 ∈ ℝ*) | |
9 | renemnf 11268 | . . . . . . . 8 ⊢ (𝐴 ∈ ℝ → 𝐴 ≠ -∞) | |
10 | xaddpnf1 13210 | . . . . . . . 8 ⊢ ((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) → (𝐴 +𝑒 +∞) = +∞) | |
11 | 8, 9, 10 | syl2anc 583 | . . . . . . 7 ⊢ (𝐴 ∈ ℝ → (𝐴 +𝑒 +∞) = +∞) |
12 | 7, 11 | sylan9eqr 2793 | . . . . . 6 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → (𝐴 +𝑒 𝐵) = +∞) |
13 | pnfnemnf 11274 | . . . . . . 7 ⊢ +∞ ≠ -∞ | |
14 | 13 | a1i 11 | . . . . . 6 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → +∞ ≠ -∞) |
15 | 12, 14 | eqnetrd 3007 | . . . . 5 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → (𝐴 +𝑒 𝐵) ≠ -∞) |
16 | 6, 15 | jaodan 955 | . . . 4 ⊢ ((𝐴 ∈ ℝ ∧ (𝐵 ∈ ℝ ∨ 𝐵 = +∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
17 | 2, 16 | sylan2b 593 | . . 3 ⊢ ((𝐴 ∈ ℝ ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
18 | oveq1 7419 | . . . . 5 ⊢ (𝐴 = +∞ → (𝐴 +𝑒 𝐵) = (+∞ +𝑒 𝐵)) | |
19 | xaddpnf2 13211 | . . . . 5 ⊢ ((𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞) → (+∞ +𝑒 𝐵) = +∞) | |
20 | 18, 19 | sylan9eq 2791 | . . . 4 ⊢ ((𝐴 = +∞ ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) = +∞) |
21 | 13 | a1i 11 | . . . 4 ⊢ ((𝐴 = +∞ ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → +∞ ≠ -∞) |
22 | 20, 21 | eqnetrd 3007 | . . 3 ⊢ ((𝐴 = +∞ ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
23 | 17, 22 | jaoian 954 | . 2 ⊢ (((𝐴 ∈ ℝ ∨ 𝐴 = +∞) ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
24 | 1, 23 | sylanb 580 | 1 ⊢ (((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ∧ wa 395 ∨ wo 844 = wceq 1540 ∈ wcel 2105 ≠ wne 2939 (class class class)co 7412 ℝcr 11112 + caddc 11116 +∞cpnf 11250 -∞cmnf 11251 ℝ*cxr 11252 +𝑒 cxad 13095 |
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 1912 ax-6 1970 ax-7 2010 ax-8 2107 ax-9 2115 ax-10 2136 ax-11 2153 ax-12 2170 ax-ext 2702 ax-sep 5300 ax-nul 5307 ax-pow 5364 ax-pr 5428 ax-un 7728 ax-cnex 11169 ax-resscn 11170 ax-1cn 11171 ax-icn 11172 ax-addcl 11173 ax-addrcl 11174 ax-mulcl 11175 ax-i2m1 11181 |
This theorem depends on definitions: df-bi 206 df-an 396 df-or 845 df-3or 1087 df-3an 1088 df-tru 1543 df-fal 1553 df-ex 1781 df-nf 1785 df-sb 2067 df-mo 2533 df-eu 2562 df-clab 2709 df-cleq 2723 df-clel 2809 df-nfc 2884 df-ne 2940 df-nel 3046 df-ral 3061 df-rex 3070 df-rab 3432 df-v 3475 df-sbc 3779 df-csb 3895 df-dif 3952 df-un 3954 df-in 3956 df-ss 3966 df-nul 4324 df-if 4530 df-pw 4605 df-sn 4630 df-pr 4632 df-op 4636 df-uni 4910 df-br 5150 df-opab 5212 df-mpt 5233 df-id 5575 df-xp 5683 df-rel 5684 df-cnv 5685 df-co 5686 df-dm 5687 df-rn 5688 df-res 5689 df-ima 5690 df-iota 6496 df-fun 6546 df-fn 6547 df-f 6548 df-f1 6549 df-fo 6550 df-f1o 6551 df-fv 6552 df-ov 7415 df-oprab 7416 df-mpo 7417 df-er 8706 df-en 8943 df-dom 8944 df-sdom 8945 df-pnf 11255 df-mnf 11256 df-xr 11257 df-xadd 13098 |
This theorem is referenced by: xaddass 13233 xlt2add 13244 xadd4d 13287 xrs1mnd 21184 |
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