Theorem receu 5621

Description: Existential uniqueness of reciprocals. Theorem I.8 of [Apostol] p. 18.

Hypotheses

Ref	Expression
receu.1	|- A e. CC
receu.2	|- B e. CC
receu.3	|- A =/= 0

Assertion

Ref	Expression
receu	|- E!x e. CC (A x. x) = B

Distinct variable groups:   x,A   x,B

Proof of Theorem receu

Step	Hyp	Ref	Expression
1		opreq2 3908	. . . 4 |- (x = y -> (A x. x) = (A x. y))
2	1	eqeq1d 1459	. . 3 |- (x = y -> ((A x. x) = B <-> (A x. y) = B))
3	2	reu4 1905	. 2 |- (E!x e. CC (A x. x) = B <-> (E.x e. CC (A x. x) = B /\ A.x e. CC A.y e. CC (((A x. x) = B /\ (A x. y) = B) -> x = y)))
4		receu.1	. . . 4 |- A e. CC
5		receu.3	. . . 4 |- A =/= 0
6	4, 5	recex 5609	. . 3 |- E.y e. CC (A x. y) = 1
7		receu.2	. . . . . . 7 |- B e. CC
8		axmulcl 5196	. . . . . . 7 |- ((y e. CC /\ B e. CC) -> (y x. B) e. CC)
9	7, 8	mpan2 693	. . . . . 6 |- (y e. CC -> (y x. B) e. CC)
10		risset 1661	. . . . . 6 |- ((y x. B) e. CC <-> E.x e. CC x = (y x. B))
11	9, 10	sylib 198	. . . . 5 |- (y e. CC -> E.x e. CC x = (y x. B))
12		opreq2 3908	. . . . . . . . . . . . 13 |- (x = (y x. B) -> (A x. x) = (A x. (y x. B)))
13		axmulass 5201	. . . . . . . . . . . . . . 15 |- ((A e. CC /\ y e. CC /\ B e. CC) -> ((A x. y) x. B) = (A x. (y x. B)))
14	4, 7, 13	mp3an13 903	. . . . . . . . . . . . . 14 |- (y e. CC -> ((A x. y) x. B) = (A x. (y x. B)))
15	14	eqcomd 1456	. . . . . . . . . . . . 13 |- (y e. CC -> (A x. (y x. B)) = ((A x. y) x. B))
16	12, 15	sylan9eqr 1505	. . . . . . . . . . . 12 |- ((y e. CC /\ x = (y x. B)) -> (A x. x) = ((A x. y) x. B))
17		opreq1 3907	. . . . . . . . . . . . 13 |- ((A x. y) = 1 -> ((A x. y) x. B) = (1 x. B))
18	7	mulid2 5256	. . . . . . . . . . . . 13 |- (1 x. B) = B
19	17, 18	syl6eq 1499	. . . . . . . . . . . 12 |- ((A x. y) = 1 -> ((A x. y) x. B) = B)
20	16, 19	sylan9eqr 1505	. . . . . . . . . . 11 |- (((A x. y) = 1 /\ (y e. CC /\ x = (y x. B))) -> (A x. x) = B)
21	20	exp32 377	. . . . . . . . . 10 |- ((A x. y) = 1 -> (y e. CC -> (x = (y x. B) -> (A x. x) = B)))
22	21	impcom 351	. . . . . . . . 9 |- ((y e. CC /\ (A x. y) = 1) -> (x = (y x. B) -> (A x. x) = B))
23	22	a1d 12	. . . . . . . 8 |- ((y e. CC /\ (A x. y) = 1) -> (x e. CC -> (x = (y x. B) -> (A x. x) = B)))
24	23	r19.21aiv 1689	. . . . . . 7 |- ((y e. CC /\ (A x. y) = 1) -> A.x e. CC (x = (y x. B) -> (A x. x) = B))
25	24	ex 373	. . . . . 6 |- (y e. CC -> ((A x. y) = 1 -> A.x e. CC (x = (y x. B) -> (A x. x) = B)))
26		r19.22 1707	. . . . . 6 |- (A.x e. CC (x = (y x. B) -> (A x. x) = B) -> (E.x e. CC x = (y x. B) -> E.x e. CC (A x. x) = B))
27	25, 26	syl6 22	. . . . 5 |- (y e. CC -> ((A x. y) = 1 -> (E.x e. CC x = (y x. B) -> E.x e. CC (A x. x) = B)))
28	11, 27	mpid 47	. . . 4 |- (y e. CC -> ((A x. y) = 1 -> E.x e. CC (A x. x) = B))
29	28	r19.23aiv 1719	. . 3 |- (E.y e. CC (A x. y) = 1 -> E.x e. CC (A x. x) = B)
30	6, 29	ax-mp 7	. 2 |- E.x e. CC (A x. x) = B
31	5	mulcant2 5611	. . . . 5 |- ((A e. CC /\ x e. CC /\ y e. CC) -> ((A x. x) = (A x. y) <-> x = y))
32		eqtr3t 1470	. . . . 5 |- (((A x. x) = B /\ (A x. y) = B) -> (A x. x) = (A x. y))
33	31, 32	syl5bi 208	. . . 4 |- ((A e. CC /\ x e. CC /\ y e. CC) -> (((A x. x) = B /\ (A x. y) = B) -> x = y))
34	4, 33	mp3an1 899	. . 3 |- ((x e. CC /\ y e. CC) -> (((A x. x) = B /\ (A x. y) = B) -> x = y))
35	34	rgen2a 1675	. 2 |- A.x e. CC A.y e. CC (((A x. x) = B /\ (A x. y) = B) -> x = y)
36	3, 30, 35	mpbir2an 727	1 |- E!x e. CC (A x. x) = B

Syntax hints:   -> wi 3   /\ wa 223   /\ w3a 772   = wceq 1099   e. wcel 1105   =/= wne 1561  A.wral 1621  E.wrex 1622  E!wreu 1623  (class class class)co 3902  CCcc 5155  0cc0 5157  1c1 5158   x. cmul 5162

This theorem is referenced by:  divmul 5625  divcl 5630

This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-4 951  ax-5 952  ax-6 953  ax-7 954  ax-gen 955  ax-8 1101  ax-9 1102  ax-10 1103  ax-12 1104  ax-13 1107  ax-14 1108  ax-11 1180  ax-17 1190  ax-16 1194  ax-11o 1202  ax-ext 1436  ax-rep 2661  ax-sep 2671  ax-nul 2678  ax-pow 2710  ax-pr 2747  ax-un 2830  ax-inf2 4549

This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3or 773  df-3an 774  df-ex 957  df-sb 1155  df-eu 1359  df-mo 1360  df-clab 1441  df-cleq 1446  df-clel 1449  df-ne 1563  df-nel 1564  df-ral 1625  df-rex 1626  df-reu 1627  df-rab 1628  df-v 1787  df-sbc 1913  df-csb 1973  df-dif 2020  df-un 2021  df-in 2022  df-ss 2024  df-pss 2026  df-nul 2252  df-if 2333  df-pw 2373  df-sn 2383  df-pr 2384  df-tp 2386  df-op 2387  df-uni 2472  df-int 2502  df-iun 2536  df-br 2588  df-opab 2635  df-tr 2649  df-eprel 2794  df-id 2797  df-po 2804  df-so 2814  df-fr 2880  df-we 2897  df-ord 2914  df-on 2915  df-lim 2916  df-suc 2917  df-om 3095  df-xp 3147  df-rel 3148  df-cnv 3149  df-co 3150  df-dm 3151  df-rn 3152  df-res 3153  df-ima 3154  df-fun 3155  df-fn 3156  df-f 3157  df-f1 3158  df-fo 3159  df-f1o 3160  df-fv 3161  df-rdg 3871  df-opr 3904  df-oprab 3905  df-1st 4017  df-2nd 4018  df-1o 4071  df-oadd 4073  df-omul 4074  df-er 4199  df-ec 4201  df-qs 4204  df-en 4305  df-dom 4306  df-sdom 4307  df-ni 4923  df-pli 4924  df-mi 4925  df-lti 4926  df-plpq 4958  df-mpq 4959  df-enq 4960  df-nq 4961  df-plq 4962  df-mq 4963  df-rq 4964  df-ltq 4965  df-1q 4966  df-np 5009  df-1p 5010  df-plp 5011  df-mp 5012  df-ltp 5013  df-plpr 5087  df-mpr 5088  df-enr 5089  df-nr 5090  df-plr 5091  df-mr 5092  df-ltr 5093  df-0r 5094  df-1r 5095  df-m1r 5096  df-c 5163  df-0 5164  df-1 5165  df-i 5166  df-r 5167  df-plus 5168  df-mul 5169  df-lt 5170  df-sub 5279  df-neg 5281  df-pnf 5410  df-mnf 5411  df-xr 5412  df-ltxr 5413  df-le 5414

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