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| Mirrors > Home > ILE Home > Th. List > 0cnALT | GIF version | ||
| Description: Alternate proof of 0cn 8170. (Contributed by NM, 19-Feb-2005.) (Revised by Mario Carneiro, 27-May-2016.) (Proof modification is discouraged.) (New usage is discouraged.) |
| Ref | Expression |
|---|---|
| 0cnALT | ⊢ 0 ∈ ℂ |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ax-icn 8126 | . . 3 ⊢ i ∈ ℂ | |
| 2 | cnegex 8356 | . . 3 ⊢ (i ∈ ℂ → ∃𝑥 ∈ ℂ (i + 𝑥) = 0) | |
| 3 | 1, 2 | ax-mp 5 | . 2 ⊢ ∃𝑥 ∈ ℂ (i + 𝑥) = 0 |
| 4 | addcl 8156 | . . . . 5 ⊢ ((i ∈ ℂ ∧ 𝑥 ∈ ℂ) → (i + 𝑥) ∈ ℂ) | |
| 5 | 1, 4 | mpan 424 | . . . 4 ⊢ (𝑥 ∈ ℂ → (i + 𝑥) ∈ ℂ) |
| 6 | eleq1 2294 | . . . 4 ⊢ ((i + 𝑥) = 0 → ((i + 𝑥) ∈ ℂ ↔ 0 ∈ ℂ)) | |
| 7 | 5, 6 | syl5ibcom 155 | . . 3 ⊢ (𝑥 ∈ ℂ → ((i + 𝑥) = 0 → 0 ∈ ℂ)) |
| 8 | 7 | rexlimiv 2644 | . 2 ⊢ (∃𝑥 ∈ ℂ (i + 𝑥) = 0 → 0 ∈ ℂ) |
| 9 | 3, 8 | ax-mp 5 | 1 ⊢ 0 ∈ ℂ |
| Colors of variables: wff set class |
| Syntax hints: = wceq 1397 ∈ wcel 2202 ∃wrex 2511 (class class class)co 6017 ℂcc 8029 0cc0 8031 ici 8033 + caddc 8034 |
| 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-io 716 ax-5 1495 ax-7 1496 ax-gen 1497 ax-ie1 1541 ax-ie2 1542 ax-8 1552 ax-10 1553 ax-11 1554 ax-i12 1555 ax-bndl 1557 ax-4 1558 ax-17 1574 ax-i9 1578 ax-ial 1582 ax-i5r 1583 ax-ext 2213 ax-resscn 8123 ax-1cn 8124 ax-icn 8126 ax-addcl 8127 ax-addrcl 8128 ax-mulcl 8129 ax-addcom 8131 ax-addass 8133 ax-distr 8135 ax-i2m1 8136 ax-0id 8139 ax-rnegex 8140 ax-cnre 8142 |
| This theorem depends on definitions: df-bi 117 df-3an 1006 df-tru 1400 df-nf 1509 df-sb 1811 df-clab 2218 df-cleq 2224 df-clel 2227 df-nfc 2363 df-ral 2515 df-rex 2516 df-v 2804 df-un 3204 df-in 3206 df-ss 3213 df-sn 3675 df-pr 3676 df-op 3678 df-uni 3894 df-br 4089 df-iota 5286 df-fv 5334 df-ov 6020 |
| This theorem is referenced by: (None) |
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