Theorem receuap 8816

Description: Existential uniqueness of reciprocals. (Contributed by Jim Kingdon, 21-Feb-2020.)

Assertion

Ref	Expression
receuap	⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐵 # 0) → ∃!𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴)

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem receuap

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		recexap 8800	. . . 4 ⊢ ((𝐵 ∈ ℂ ∧ 𝐵 # 0) → ∃𝑦 ∈ ℂ (𝐵 · 𝑦) = 1)
2	1	3adant1 1039	. . 3 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐵 # 0) → ∃𝑦 ∈ ℂ (𝐵 · 𝑦) = 1)
3		simprl 529	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → 𝑦 ∈ ℂ)
4		simpll 527	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → 𝐴 ∈ ℂ)
5	3, 4	mulcld 8167	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → (𝑦 · 𝐴) ∈ ℂ)
6		oveq1 6008	. . . . . . . 8 ⊢ ((𝐵 · 𝑦) = 1 → ((𝐵 · 𝑦) · 𝐴) = (1 · 𝐴))
7	6	ad2antll 491	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → ((𝐵 · 𝑦) · 𝐴) = (1 · 𝐴))
8		simplr 528	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → 𝐵 ∈ ℂ)
9	8, 3, 4	mulassd 8170	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → ((𝐵 · 𝑦) · 𝐴) = (𝐵 · (𝑦 · 𝐴)))
10	4	mulid2d 8165	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → (1 · 𝐴) = 𝐴)
11	7, 9, 10	3eqtr3d 2270	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → (𝐵 · (𝑦 · 𝐴)) = 𝐴)
12		oveq2 6009	. . . . . . . 8 ⊢ (𝑥 = (𝑦 · 𝐴) → (𝐵 · 𝑥) = (𝐵 · (𝑦 · 𝐴)))
13	12	eqeq1d 2238	. . . . . . 7 ⊢ (𝑥 = (𝑦 · 𝐴) → ((𝐵 · 𝑥) = 𝐴 ↔ (𝐵 · (𝑦 · 𝐴)) = 𝐴))
14	13	rspcev 2907	. . . . . 6 ⊢ (((𝑦 · 𝐴) ∈ ℂ ∧ (𝐵 · (𝑦 · 𝐴)) = 𝐴) → ∃𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴)
15	5, 11, 14	syl2anc 411	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝑦 ∈ ℂ ∧ (𝐵 · 𝑦) = 1)) → ∃𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴)
16	15	rexlimdvaa 2649	. . . 4 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (∃𝑦 ∈ ℂ (𝐵 · 𝑦) = 1 → ∃𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴))
17	16	3adant3 1041	. . 3 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐵 # 0) → (∃𝑦 ∈ ℂ (𝐵 · 𝑦) = 1 → ∃𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴))
18	2, 17	mpd 13	. 2 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐵 # 0) → ∃𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴)
19		eqtr3 2249	. . . . . . 7 ⊢ (((𝐵 · 𝑥) = 𝐴 ∧ (𝐵 · 𝑦) = 𝐴) → (𝐵 · 𝑥) = (𝐵 · 𝑦))
20		mulcanap 8812	. . . . . . 7 ⊢ ((𝑥 ∈ ℂ ∧ 𝑦 ∈ ℂ ∧ (𝐵 ∈ ℂ ∧ 𝐵 # 0)) → ((𝐵 · 𝑥) = (𝐵 · 𝑦) ↔ 𝑥 = 𝑦))
21	19, 20	imbitrid 154	. . . . . 6 ⊢ ((𝑥 ∈ ℂ ∧ 𝑦 ∈ ℂ ∧ (𝐵 ∈ ℂ ∧ 𝐵 # 0)) → (((𝐵 · 𝑥) = 𝐴 ∧ (𝐵 · 𝑦) = 𝐴) → 𝑥 = 𝑦))
22	21	3expa 1227	. . . . 5 ⊢ (((𝑥 ∈ ℂ ∧ 𝑦 ∈ ℂ) ∧ (𝐵 ∈ ℂ ∧ 𝐵 # 0)) → (((𝐵 · 𝑥) = 𝐴 ∧ (𝐵 · 𝑦) = 𝐴) → 𝑥 = 𝑦))
23	22	expcom 116	. . . 4 ⊢ ((𝐵 ∈ ℂ ∧ 𝐵 # 0) → ((𝑥 ∈ ℂ ∧ 𝑦 ∈ ℂ) → (((𝐵 · 𝑥) = 𝐴 ∧ (𝐵 · 𝑦) = 𝐴) → 𝑥 = 𝑦)))
24	23	3adant1 1039	. . 3 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐵 # 0) → ((𝑥 ∈ ℂ ∧ 𝑦 ∈ ℂ) → (((𝐵 · 𝑥) = 𝐴 ∧ (𝐵 · 𝑦) = 𝐴) → 𝑥 = 𝑦)))
25	24	ralrimivv 2611	. 2 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐵 # 0) → ∀𝑥 ∈ ℂ ∀𝑦 ∈ ℂ (((𝐵 · 𝑥) = 𝐴 ∧ (𝐵 · 𝑦) = 𝐴) → 𝑥 = 𝑦))
26		oveq2 6009	. . . 4 ⊢ (𝑥 = 𝑦 → (𝐵 · 𝑥) = (𝐵 · 𝑦))
27	26	eqeq1d 2238	. . 3 ⊢ (𝑥 = 𝑦 → ((𝐵 · 𝑥) = 𝐴 ↔ (𝐵 · 𝑦) = 𝐴))
28	27	reu4 2997	. 2 ⊢ (∃!𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴 ↔ (∃𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴 ∧ ∀𝑥 ∈ ℂ ∀𝑦 ∈ ℂ (((𝐵 · 𝑥) = 𝐴 ∧ (𝐵 · 𝑦) = 𝐴) → 𝑥 = 𝑦)))
29	18, 25, 28	sylanbrc 417	1 ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐵 # 0) → ∃!𝑥 ∈ ℂ (𝐵 · 𝑥) = 𝐴)

Syntax hints:   → wi 4   ∧ wa 104   ∧ w3a 1002   = wceq 1395   ∈ wcel 2200  ∀wral 2508  ∃wrex 2509  ∃!wreu 2510   class class class wbr 4083  (class class class)co 6001  ℂcc 7997  0cc0 7999  1c1 8000   · cmul 8004   # cap 8728

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 617  ax-in2 618  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-13 2202  ax-14 2203  ax-ext 2211  ax-sep 4202  ax-pow 4258  ax-pr 4293  ax-un 4524  ax-setind 4629  ax-cnex 8090  ax-resscn 8091  ax-1cn 8092  ax-1re 8093  ax-icn 8094  ax-addcl 8095  ax-addrcl 8096  ax-mulcl 8097  ax-mulrcl 8098  ax-addcom 8099  ax-mulcom 8100  ax-addass 8101  ax-mulass 8102  ax-distr 8103  ax-i2m1 8104  ax-0lt1 8105  ax-1rid 8106  ax-0id 8107  ax-rnegex 8108  ax-precex 8109  ax-cnre 8110  ax-pre-ltirr 8111  ax-pre-ltwlin 8112  ax-pre-lttrn 8113  ax-pre-apti 8114  ax-pre-ltadd 8115  ax-pre-mulgt0 8116  ax-pre-mulext 8117

This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-nel 2496  df-ral 2513  df-rex 2514  df-reu 2515  df-rmo 2516  df-rab 2517  df-v 2801  df-sbc 3029  df-dif 3199  df-un 3201  df-in 3203  df-ss 3210  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3889  df-br 4084  df-opab 4146  df-id 4384  df-po 4387  df-iso 4388  df-xp 4725  df-rel 4726  df-cnv 4727  df-co 4728  df-dm 4729  df-iota 5278  df-fun 5320  df-fv 5326  df-riota 5954  df-ov 6004  df-oprab 6005  df-mpo 6006  df-pnf 8183  df-mnf 8184  df-xr 8185  df-ltxr 8186  df-le 8187  df-sub 8319  df-neg 8320  df-reap 8722  df-ap 8729

This theorem is referenced by:  divvalap  8821  divmulap  8822  divclap  8825