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Mirrors > Home > ILE Home > Th. List > xaddpnf2 | GIF version |
Description: Addition of positive infinity on the left. (Contributed by Mario Carneiro, 20-Aug-2015.) |
Ref | Expression |
---|---|
xaddpnf2 | ⊢ ((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) → (+∞ +𝑒 𝐴) = +∞) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | pnfxr 7942 | . . 3 ⊢ +∞ ∈ ℝ* | |
2 | xaddval 9772 | . . 3 ⊢ ((+∞ ∈ ℝ* ∧ 𝐴 ∈ ℝ*) → (+∞ +𝑒 𝐴) = if(+∞ = +∞, if(𝐴 = -∞, 0, +∞), if(+∞ = -∞, if(𝐴 = +∞, 0, -∞), if(𝐴 = +∞, +∞, if(𝐴 = -∞, -∞, (+∞ + 𝐴)))))) | |
3 | 1, 2 | mpan 421 | . 2 ⊢ (𝐴 ∈ ℝ* → (+∞ +𝑒 𝐴) = if(+∞ = +∞, if(𝐴 = -∞, 0, +∞), if(+∞ = -∞, if(𝐴 = +∞, 0, -∞), if(𝐴 = +∞, +∞, if(𝐴 = -∞, -∞, (+∞ + 𝐴)))))) |
4 | eqid 2164 | . . . 4 ⊢ +∞ = +∞ | |
5 | 4 | iftruei 3521 | . . 3 ⊢ if(+∞ = +∞, if(𝐴 = -∞, 0, +∞), if(+∞ = -∞, if(𝐴 = +∞, 0, -∞), if(𝐴 = +∞, +∞, if(𝐴 = -∞, -∞, (+∞ + 𝐴))))) = if(𝐴 = -∞, 0, +∞) |
6 | ifnefalse 3526 | . . 3 ⊢ (𝐴 ≠ -∞ → if(𝐴 = -∞, 0, +∞) = +∞) | |
7 | 5, 6 | syl5eq 2209 | . 2 ⊢ (𝐴 ≠ -∞ → if(+∞ = +∞, if(𝐴 = -∞, 0, +∞), if(+∞ = -∞, if(𝐴 = +∞, 0, -∞), if(𝐴 = +∞, +∞, if(𝐴 = -∞, -∞, (+∞ + 𝐴))))) = +∞) |
8 | 3, 7 | sylan9eq 2217 | 1 ⊢ ((𝐴 ∈ ℝ* ∧ 𝐴 ≠ -∞) → (+∞ +𝑒 𝐴) = +∞) |
Colors of variables: wff set class |
Syntax hints: → wi 4 ∧ wa 103 = wceq 1342 ∈ wcel 2135 ≠ wne 2334 ifcif 3515 (class class class)co 5836 0cc0 7744 + caddc 7747 +∞cpnf 7921 -∞cmnf 7922 ℝ*cxr 7923 +𝑒 cxad 9697 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 105 ax-ia2 106 ax-ia3 107 ax-in1 604 ax-in2 605 ax-io 699 ax-5 1434 ax-7 1435 ax-gen 1436 ax-ie1 1480 ax-ie2 1481 ax-8 1491 ax-10 1492 ax-11 1493 ax-i12 1494 ax-bndl 1496 ax-4 1497 ax-17 1513 ax-i9 1517 ax-ial 1521 ax-i5r 1522 ax-13 2137 ax-14 2138 ax-ext 2146 ax-sep 4094 ax-pow 4147 ax-pr 4181 ax-un 4405 ax-setind 4508 ax-cnex 7835 ax-resscn 7836 ax-1re 7838 ax-addrcl 7841 ax-rnegex 7853 |
This theorem depends on definitions: df-bi 116 df-dc 825 df-3or 968 df-3an 969 df-tru 1345 df-fal 1348 df-nf 1448 df-sb 1750 df-eu 2016 df-mo 2017 df-clab 2151 df-cleq 2157 df-clel 2160 df-nfc 2295 df-ne 2335 df-nel 2430 df-ral 2447 df-rex 2448 df-rab 2451 df-v 2723 df-sbc 2947 df-dif 3113 df-un 3115 df-in 3117 df-ss 3124 df-if 3516 df-pw 3555 df-sn 3576 df-pr 3577 df-op 3579 df-uni 3784 df-br 3977 df-opab 4038 df-id 4265 df-xp 4604 df-rel 4605 df-cnv 4606 df-co 4607 df-dm 4608 df-iota 5147 df-fun 5184 df-fv 5190 df-ov 5839 df-oprab 5840 df-mpo 5841 df-pnf 7926 df-mnf 7927 df-xr 7928 df-xadd 9700 |
This theorem is referenced by: xaddnemnf 9784 xaddcom 9788 xaddid1 9789 xnn0xadd0 9794 xnegdi 9795 xaddass 9796 xleadd1a 9800 xltadd1 9803 xposdif 9809 xleaddadd 9814 xrmaxadd 11188 xrbdtri 11203 isxmet2d 12895 |
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