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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 12494 | . 2 ⊢ ((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) ↔ (𝐴 ∈ ℝ ∨ 𝐴 = +∞)) | |
2 | xrnemnf 12494 | . . . 4 ⊢ ((𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞) ↔ (𝐵 ∈ ℝ ∨ 𝐵 = +∞)) | |
3 | rexadd 12607 | . . . . . . 7 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 +𝑒 𝐵) = (𝐴 + 𝐵)) | |
4 | readdcl 10601 | . . . . . . 7 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 + 𝐵) ∈ ℝ) | |
5 | 3, 4 | eqeltrd 2911 | . . . . . 6 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 +𝑒 𝐵) ∈ ℝ) |
6 | 5 | renemnfd 10674 | . . . . 5 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 +𝑒 𝐵) ≠ -∞) |
7 | oveq2 7145 | . . . . . . 7 ⊢ (𝐵 = +∞ → (𝐴 +𝑒 𝐵) = (𝐴 +𝑒 +∞)) | |
8 | rexr 10668 | . . . . . . . 8 ⊢ (𝐴 ∈ ℝ → 𝐴 ∈ ℝ*) | |
9 | renemnf 10671 | . . . . . . . 8 ⊢ (𝐴 ∈ ℝ → 𝐴 ≠ -∞) | |
10 | xaddpnf1 12601 | . . . . . . . 8 ⊢ ((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) → (𝐴 +𝑒 +∞) = +∞) | |
11 | 8, 9, 10 | syl2anc 586 | . . . . . . 7 ⊢ (𝐴 ∈ ℝ → (𝐴 +𝑒 +∞) = +∞) |
12 | 7, 11 | sylan9eqr 2877 | . . . . . 6 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → (𝐴 +𝑒 𝐵) = +∞) |
13 | pnfnemnf 10677 | . . . . . . 7 ⊢ +∞ ≠ -∞ | |
14 | 13 | a1i 11 | . . . . . 6 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → +∞ ≠ -∞) |
15 | 12, 14 | eqnetrd 3078 | . . . . 5 ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → (𝐴 +𝑒 𝐵) ≠ -∞) |
16 | 6, 15 | jaodan 954 | . . . 4 ⊢ ((𝐴 ∈ ℝ ∧ (𝐵 ∈ ℝ ∨ 𝐵 = +∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
17 | 2, 16 | sylan2b 595 | . . 3 ⊢ ((𝐴 ∈ ℝ ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
18 | oveq1 7144 | . . . . 5 ⊢ (𝐴 = +∞ → (𝐴 +𝑒 𝐵) = (+∞ +𝑒 𝐵)) | |
19 | xaddpnf2 12602 | . . . . 5 ⊢ ((𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞) → (+∞ +𝑒 𝐵) = +∞) | |
20 | 18, 19 | sylan9eq 2875 | . . . 4 ⊢ ((𝐴 = +∞ ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) = +∞) |
21 | 13 | a1i 11 | . . . 4 ⊢ ((𝐴 = +∞ ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → +∞ ≠ -∞) |
22 | 20, 21 | eqnetrd 3078 | . . 3 ⊢ ((𝐴 = +∞ ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
23 | 17, 22 | jaoian 953 | . 2 ⊢ (((𝐴 ∈ ℝ ∨ 𝐴 = +∞) ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
24 | 1, 23 | sylanb 583 | 1 ⊢ (((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) ∧ (𝐵 ∈ ℝ* ∧ 𝐵 ≠ -∞)) → (𝐴 +𝑒 𝐵) ≠ -∞) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ∧ wa 398 ∨ wo 843 = wceq 1537 ∈ wcel 2114 ≠ wne 3011 (class class class)co 7137 ℝcr 10517 + caddc 10521 +∞cpnf 10653 -∞cmnf 10654 ℝ*cxr 10655 +𝑒 cxad 12487 |
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 1970 ax-7 2015 ax-8 2116 ax-9 2124 ax-10 2145 ax-11 2161 ax-12 2177 ax-ext 2792 ax-sep 5184 ax-nul 5191 ax-pow 5247 ax-pr 5311 ax-un 7442 ax-cnex 10574 ax-resscn 10575 ax-1cn 10576 ax-icn 10577 ax-addcl 10578 ax-addrcl 10579 ax-mulcl 10580 ax-i2m1 10586 |
This theorem depends on definitions: df-bi 209 df-an 399 df-or 844 df-3or 1084 df-3an 1085 df-tru 1540 df-ex 1781 df-nf 1785 df-sb 2070 df-mo 2622 df-eu 2653 df-clab 2799 df-cleq 2813 df-clel 2891 df-nfc 2959 df-ne 3012 df-nel 3119 df-ral 3138 df-rex 3139 df-rab 3142 df-v 3483 df-sbc 3759 df-csb 3867 df-dif 3922 df-un 3924 df-in 3926 df-ss 3935 df-nul 4275 df-if 4449 df-pw 4522 df-sn 4549 df-pr 4551 df-op 4555 df-uni 4820 df-br 5048 df-opab 5110 df-mpt 5128 df-id 5441 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 6295 df-fun 6338 df-fn 6339 df-f 6340 df-f1 6341 df-fo 6342 df-f1o 6343 df-fv 6344 df-ov 7140 df-oprab 7141 df-mpo 7142 df-er 8270 df-en 8491 df-dom 8492 df-sdom 8493 df-pnf 10658 df-mnf 10659 df-xr 10660 df-xadd 12490 |
This theorem is referenced by: xaddass 12624 xlt2add 12635 xadd4d 12678 xrs1mnd 20561 |
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