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| Mirrors > Home > ILE Home > Th. List > inelr | GIF version | ||
| Description: The imaginary unit i is not a real number. (Contributed by NM, 6-May-1999.) | 
| Ref | Expression | 
|---|---|
| inelr | ⊢ ¬ i ∈ ℝ | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | ine0 8420 | . . 3 ⊢ i ≠ 0 | |
| 2 | 1 | neii 2369 | . 2 ⊢ ¬ i = 0 | 
| 3 | 0lt1 8153 | . . . . . 6 ⊢ 0 < 1 | |
| 4 | 0re 8026 | . . . . . . 7 ⊢ 0 ∈ ℝ | |
| 5 | 1re 8025 | . . . . . . 7 ⊢ 1 ∈ ℝ | |
| 6 | 4, 5 | ltnsymi 8126 | . . . . . 6 ⊢ (0 < 1 → ¬ 1 < 0) | 
| 7 | 3, 6 | ax-mp 5 | . . . . 5 ⊢ ¬ 1 < 0 | 
| 8 | ixi 8610 | . . . . . . . 8 ⊢ (i · i) = -1 | |
| 9 | 5 | renegcli 8288 | . . . . . . . 8 ⊢ -1 ∈ ℝ | 
| 10 | 8, 9 | eqeltri 2269 | . . . . . . 7 ⊢ (i · i) ∈ ℝ | 
| 11 | 4, 10, 5 | ltadd1i 8529 | . . . . . 6 ⊢ (0 < (i · i) ↔ (0 + 1) < ((i · i) + 1)) | 
| 12 | ax-1cn 7972 | . . . . . . . 8 ⊢ 1 ∈ ℂ | |
| 13 | 12 | addlidi 8169 | . . . . . . 7 ⊢ (0 + 1) = 1 | 
| 14 | ax-i2m1 7984 | . . . . . . 7 ⊢ ((i · i) + 1) = 0 | |
| 15 | 13, 14 | breq12i 4042 | . . . . . 6 ⊢ ((0 + 1) < ((i · i) + 1) ↔ 1 < 0) | 
| 16 | 11, 15 | bitri 184 | . . . . 5 ⊢ (0 < (i · i) ↔ 1 < 0) | 
| 17 | 7, 16 | mtbir 672 | . . . 4 ⊢ ¬ 0 < (i · i) | 
| 18 | mullt0 8507 | . . . . . 6 ⊢ (((i ∈ ℝ ∧ i < 0) ∧ (i ∈ ℝ ∧ i < 0)) → 0 < (i · i)) | |
| 19 | 18 | anidms 397 | . . . . 5 ⊢ ((i ∈ ℝ ∧ i < 0) → 0 < (i · i)) | 
| 20 | 19 | ex 115 | . . . 4 ⊢ (i ∈ ℝ → (i < 0 → 0 < (i · i))) | 
| 21 | 17, 20 | mtoi 665 | . . 3 ⊢ (i ∈ ℝ → ¬ i < 0) | 
| 22 | mulgt0 8101 | . . . . . 6 ⊢ (((i ∈ ℝ ∧ 0 < i) ∧ (i ∈ ℝ ∧ 0 < i)) → 0 < (i · i)) | |
| 23 | 22 | anidms 397 | . . . . 5 ⊢ ((i ∈ ℝ ∧ 0 < i) → 0 < (i · i)) | 
| 24 | 23 | ex 115 | . . . 4 ⊢ (i ∈ ℝ → (0 < i → 0 < (i · i))) | 
| 25 | 17, 24 | mtoi 665 | . . 3 ⊢ (i ∈ ℝ → ¬ 0 < i) | 
| 26 | lttri3 8106 | . . . 4 ⊢ ((i ∈ ℝ ∧ 0 ∈ ℝ) → (i = 0 ↔ (¬ i < 0 ∧ ¬ 0 < i))) | |
| 27 | 4, 26 | mpan2 425 | . . 3 ⊢ (i ∈ ℝ → (i = 0 ↔ (¬ i < 0 ∧ ¬ 0 < i))) | 
| 28 | 21, 25, 27 | mpbir2and 946 | . 2 ⊢ (i ∈ ℝ → i = 0) | 
| 29 | 2, 28 | mto 663 | 1 ⊢ ¬ i ∈ ℝ | 
| Colors of variables: wff set class | 
| Syntax hints: ¬ wn 3 ∧ wa 104 ↔ wb 105 = wceq 1364 ∈ wcel 2167 class class class wbr 4033 (class class class)co 5922 ℝcr 7878 0cc0 7879 1c1 7880 ici 7881 + caddc 7882 · cmul 7884 < clt 8061 -cneg 8198 | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-in1 615 ax-in2 616 ax-io 710 ax-5 1461 ax-7 1462 ax-gen 1463 ax-ie1 1507 ax-ie2 1508 ax-8 1518 ax-10 1519 ax-11 1520 ax-i12 1521 ax-bndl 1523 ax-4 1524 ax-17 1540 ax-i9 1544 ax-ial 1548 ax-i5r 1549 ax-13 2169 ax-14 2170 ax-ext 2178 ax-sep 4151 ax-pow 4207 ax-pr 4242 ax-un 4468 ax-setind 4573 ax-cnex 7970 ax-resscn 7971 ax-1cn 7972 ax-1re 7973 ax-icn 7974 ax-addcl 7975 ax-addrcl 7976 ax-mulcl 7977 ax-mulrcl 7978 ax-addcom 7979 ax-mulcom 7980 ax-addass 7981 ax-distr 7983 ax-i2m1 7984 ax-0lt1 7985 ax-0id 7987 ax-rnegex 7988 ax-cnre 7990 ax-pre-ltirr 7991 ax-pre-lttrn 7993 ax-pre-apti 7994 ax-pre-ltadd 7995 ax-pre-mulgt0 7996 | 
| This theorem depends on definitions: df-bi 117 df-3an 982 df-tru 1367 df-fal 1370 df-nf 1475 df-sb 1777 df-eu 2048 df-mo 2049 df-clab 2183 df-cleq 2189 df-clel 2192 df-nfc 2328 df-ne 2368 df-nel 2463 df-ral 2480 df-rex 2481 df-reu 2482 df-rab 2484 df-v 2765 df-sbc 2990 df-dif 3159 df-un 3161 df-in 3163 df-ss 3170 df-pw 3607 df-sn 3628 df-pr 3629 df-op 3631 df-uni 3840 df-br 4034 df-opab 4095 df-id 4328 df-xp 4669 df-rel 4670 df-cnv 4671 df-co 4672 df-dm 4673 df-iota 5219 df-fun 5260 df-fv 5266 df-riota 5877 df-ov 5925 df-oprab 5926 df-mpo 5927 df-pnf 8063 df-mnf 8064 df-ltxr 8066 df-sub 8199 df-neg 8200 | 
| This theorem is referenced by: rimul 8612 | 
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