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| Mirrors > Home > ILE Home > Th. List > 0cnALT | GIF version | ||
| Description: Alternate proof of 0cn 8134. (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 8090 | . . 3 ⊢ i ∈ ℂ | |
| 2 | cnegex 8320 | . . 3 ⊢ (i ∈ ℂ → ∃𝑥 ∈ ℂ (i + 𝑥) = 0) | |
| 3 | 1, 2 | ax-mp 5 | . 2 ⊢ ∃𝑥 ∈ ℂ (i + 𝑥) = 0 |
| 4 | addcl 8120 | . . . . 5 ⊢ ((i ∈ ℂ ∧ 𝑥 ∈ ℂ) → (i + 𝑥) ∈ ℂ) | |
| 5 | 1, 4 | mpan 424 | . . . 4 ⊢ (𝑥 ∈ ℂ → (i + 𝑥) ∈ ℂ) |
| 6 | eleq1 2292 | . . . 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 2642 | . 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 1395 ∈ wcel 2200 ∃wrex 2509 (class class class)co 6000 ℂcc 7993 0cc0 7995 ici 7997 + caddc 7998 |
| 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 714 ax-5 1493 ax-7 1494 ax-gen 1495 ax-ie1 1539 ax-ie2 1540 ax-8 1550 ax-10 1551 ax-11 1552 ax-i12 1553 ax-bndl 1555 ax-4 1556 ax-17 1572 ax-i9 1576 ax-ial 1580 ax-i5r 1581 ax-ext 2211 ax-resscn 8087 ax-1cn 8088 ax-icn 8090 ax-addcl 8091 ax-addrcl 8092 ax-mulcl 8093 ax-addcom 8095 ax-addass 8097 ax-distr 8099 ax-i2m1 8100 ax-0id 8103 ax-rnegex 8104 ax-cnre 8106 |
| This theorem depends on definitions: df-bi 117 df-3an 1004 df-tru 1398 df-nf 1507 df-sb 1809 df-clab 2216 df-cleq 2222 df-clel 2225 df-nfc 2361 df-ral 2513 df-rex 2514 df-v 2801 df-un 3201 df-in 3203 df-ss 3210 df-sn 3672 df-pr 3673 df-op 3675 df-uni 3888 df-br 4083 df-iota 5277 df-fv 5325 df-ov 6003 |
| This theorem is referenced by: (None) |
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