Theorem 1idpr 10445

Description: 1 is an identity element for positive real multiplication. Theorem 9-3.7(iv) of [Gleason] p. 124. (Contributed by NM, 2-Apr-1996.) (New usage is discouraged.)

Assertion

Ref	Expression
1idpr	⊢ (𝐴 ∈ P → (𝐴 ·P 1P) = 𝐴)

Proof of Theorem 1idpr

Dummy variables 𝑥 𝑦 𝑧 𝑤 𝑣 𝑢 𝑓 𝑔 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-rex 3144	. . . . 5 ⊢ (∃𝑔 ∈ 1P 𝑥 = (𝑓 ·Q 𝑔) ↔ ∃𝑔(𝑔 ∈ 1P ∧ 𝑥 = (𝑓 ·Q 𝑔)))
2		19.42v 1950	. . . . . 6 ⊢ (∃𝑔(𝑥 <Q 𝑓 ∧ 𝑥 = (𝑓 ·Q 𝑔)) ↔ (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔)))
3		elprnq 10407	. . . . . . . . . 10 ⊢ ((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) → 𝑓 ∈ Q)
4		breq1 5061	. . . . . . . . . . 11 ⊢ (𝑥 = (𝑓 ·Q 𝑔) → (𝑥 <Q 𝑓 ↔ (𝑓 ·Q 𝑔) <Q 𝑓))
5		df-1p 10398	. . . . . . . . . . . . 13 ⊢ 1P = {𝑔 ∣ 𝑔 <Q 1Q}
6	5	abeq2i 2948	. . . . . . . . . . . 12 ⊢ (𝑔 ∈ 1P ↔ 𝑔 <Q 1Q)
7		ltmnq 10388	. . . . . . . . . . . . 13 ⊢ (𝑓 ∈ Q → (𝑔 <Q 1Q ↔ (𝑓 ·Q 𝑔) <Q (𝑓 ·Q 1Q)))
8		mulidnq 10379	. . . . . . . . . . . . . 14 ⊢ (𝑓 ∈ Q → (𝑓 ·Q 1Q) = 𝑓)
9	8	breq2d 5070	. . . . . . . . . . . . 13 ⊢ (𝑓 ∈ Q → ((𝑓 ·Q 𝑔) <Q (𝑓 ·Q 1Q) ↔ (𝑓 ·Q 𝑔) <Q 𝑓))
10	7, 9	bitrd 281	. . . . . . . . . . . 12 ⊢ (𝑓 ∈ Q → (𝑔 <Q 1Q ↔ (𝑓 ·Q 𝑔) <Q 𝑓))
11	6, 10	syl5rbb 286	. . . . . . . . . . 11 ⊢ (𝑓 ∈ Q → ((𝑓 ·Q 𝑔) <Q 𝑓 ↔ 𝑔 ∈ 1P))
12	4, 11	sylan9bbr 513	. . . . . . . . . 10 ⊢ ((𝑓 ∈ Q ∧ 𝑥 = (𝑓 ·Q 𝑔)) → (𝑥 <Q 𝑓 ↔ 𝑔 ∈ 1P))
13	3, 12	sylan 582	. . . . . . . . 9 ⊢ (((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) ∧ 𝑥 = (𝑓 ·Q 𝑔)) → (𝑥 <Q 𝑓 ↔ 𝑔 ∈ 1P))
14	13	ex 415	. . . . . . . 8 ⊢ ((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) → (𝑥 = (𝑓 ·Q 𝑔) → (𝑥 <Q 𝑓 ↔ 𝑔 ∈ 1P)))
15	14	pm5.32rd 580	. . . . . . 7 ⊢ ((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) → ((𝑥 <Q 𝑓 ∧ 𝑥 = (𝑓 ·Q 𝑔)) ↔ (𝑔 ∈ 1P ∧ 𝑥 = (𝑓 ·Q 𝑔))))
16	15	exbidv 1918	. . . . . 6 ⊢ ((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) → (∃𝑔(𝑥 <Q 𝑓 ∧ 𝑥 = (𝑓 ·Q 𝑔)) ↔ ∃𝑔(𝑔 ∈ 1P ∧ 𝑥 = (𝑓 ·Q 𝑔))))
17	2, 16	syl5rbbr 288	. . . . 5 ⊢ ((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) → (∃𝑔(𝑔 ∈ 1P ∧ 𝑥 = (𝑓 ·Q 𝑔)) ↔ (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔))))
18	1, 17	syl5bb 285	. . . 4 ⊢ ((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) → (∃𝑔 ∈ 1P 𝑥 = (𝑓 ·Q 𝑔) ↔ (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔))))
19	18	rexbidva 3296	. . 3 ⊢ (𝐴 ∈ P → (∃𝑓 ∈ 𝐴 ∃𝑔 ∈ 1P 𝑥 = (𝑓 ·Q 𝑔) ↔ ∃𝑓 ∈ 𝐴 (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔))))
20		1pr 10431	. . . 4 ⊢ 1P ∈ P
21		df-mp 10400	. . . . 5 ⊢ ·P = (𝑦 ∈ P, 𝑧 ∈ P ↦ {𝑤 ∣ ∃𝑢 ∈ 𝑦 ∃𝑣 ∈ 𝑧 𝑤 = (𝑢 ·Q 𝑣)})
22		mulclnq 10363	. . . . 5 ⊢ ((𝑢 ∈ Q ∧ 𝑣 ∈ Q) → (𝑢 ·Q 𝑣) ∈ Q)
23	21, 22	genpelv 10416	. . . 4 ⊢ ((𝐴 ∈ P ∧ 1P ∈ P) → (𝑥 ∈ (𝐴 ·P 1P) ↔ ∃𝑓 ∈ 𝐴 ∃𝑔 ∈ 1P 𝑥 = (𝑓 ·Q 𝑔)))
24	20, 23	mpan2 689	. . 3 ⊢ (𝐴 ∈ P → (𝑥 ∈ (𝐴 ·P 1P) ↔ ∃𝑓 ∈ 𝐴 ∃𝑔 ∈ 1P 𝑥 = (𝑓 ·Q 𝑔)))
25		prnmax 10411	. . . . . 6 ⊢ ((𝐴 ∈ P ∧ 𝑥 ∈ 𝐴) → ∃𝑓 ∈ 𝐴 𝑥 <Q 𝑓)
26		ltrelnq 10342	. . . . . . . . . . 11 ⊢ <Q ⊆ (Q × Q)
27	26	brel 5611	. . . . . . . . . 10 ⊢ (𝑥 <Q 𝑓 → (𝑥 ∈ Q ∧ 𝑓 ∈ Q))
28		vex 3497	. . . . . . . . . . . . . 14 ⊢ 𝑓 ∈ V
29		vex 3497	. . . . . . . . . . . . . 14 ⊢ 𝑥 ∈ V
30		fvex 6677	. . . . . . . . . . . . . 14 ⊢ (*Q‘𝑓) ∈ V
31		mulcomnq 10369	. . . . . . . . . . . . . 14 ⊢ (𝑦 ·Q 𝑧) = (𝑧 ·Q 𝑦)
32		mulassnq 10375	. . . . . . . . . . . . . 14 ⊢ ((𝑦 ·Q 𝑧) ·Q 𝑤) = (𝑦 ·Q (𝑧 ·Q 𝑤))
33	28, 29, 30, 31, 32	caov12 7370	. . . . . . . . . . . . 13 ⊢ (𝑓 ·Q (𝑥 ·Q (*Q‘𝑓))) = (𝑥 ·Q (𝑓 ·Q (*Q‘𝑓)))
34		recidnq 10381	. . . . . . . . . . . . . 14 ⊢ (𝑓 ∈ Q → (𝑓 ·Q (*Q‘𝑓)) = 1Q)
35	34	oveq2d 7166	. . . . . . . . . . . . 13 ⊢ (𝑓 ∈ Q → (𝑥 ·Q (𝑓 ·Q (*Q‘𝑓))) = (𝑥 ·Q 1Q))
36	33, 35	syl5eq 2868	. . . . . . . . . . . 12 ⊢ (𝑓 ∈ Q → (𝑓 ·Q (𝑥 ·Q (*Q‘𝑓))) = (𝑥 ·Q 1Q))
37		mulidnq 10379	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ Q → (𝑥 ·Q 1Q) = 𝑥)
38	36, 37	sylan9eqr 2878	. . . . . . . . . . 11 ⊢ ((𝑥 ∈ Q ∧ 𝑓 ∈ Q) → (𝑓 ·Q (𝑥 ·Q (*Q‘𝑓))) = 𝑥)
39	38	eqcomd 2827	. . . . . . . . . 10 ⊢ ((𝑥 ∈ Q ∧ 𝑓 ∈ Q) → 𝑥 = (𝑓 ·Q (𝑥 ·Q (*Q‘𝑓))))
40		ovex 7183	. . . . . . . . . . 11 ⊢ (𝑥 ·Q (*Q‘𝑓)) ∈ V
41		oveq2 7158	. . . . . . . . . . . 12 ⊢ (𝑔 = (𝑥 ·Q (*Q‘𝑓)) → (𝑓 ·Q 𝑔) = (𝑓 ·Q (𝑥 ·Q (*Q‘𝑓))))
42	41	eqeq2d 2832	. . . . . . . . . . 11 ⊢ (𝑔 = (𝑥 ·Q (*Q‘𝑓)) → (𝑥 = (𝑓 ·Q 𝑔) ↔ 𝑥 = (𝑓 ·Q (𝑥 ·Q (*Q‘𝑓)))))
43	40, 42	spcev 3606	. . . . . . . . . 10 ⊢ (𝑥 = (𝑓 ·Q (𝑥 ·Q (*Q‘𝑓))) → ∃𝑔 𝑥 = (𝑓 ·Q 𝑔))
44	27, 39, 43	3syl 18	. . . . . . . . 9 ⊢ (𝑥 <Q 𝑓 → ∃𝑔 𝑥 = (𝑓 ·Q 𝑔))
45	44	a1i 11	. . . . . . . 8 ⊢ (𝑓 ∈ 𝐴 → (𝑥 <Q 𝑓 → ∃𝑔 𝑥 = (𝑓 ·Q 𝑔)))
46	45	ancld 553	. . . . . . 7 ⊢ (𝑓 ∈ 𝐴 → (𝑥 <Q 𝑓 → (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔))))
47	46	reximia 3242	. . . . . 6 ⊢ (∃𝑓 ∈ 𝐴 𝑥 <Q 𝑓 → ∃𝑓 ∈ 𝐴 (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔)))
48	25, 47	syl 17	. . . . 5 ⊢ ((𝐴 ∈ P ∧ 𝑥 ∈ 𝐴) → ∃𝑓 ∈ 𝐴 (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔)))
49	48	ex 415	. . . 4 ⊢ (𝐴 ∈ P → (𝑥 ∈ 𝐴 → ∃𝑓 ∈ 𝐴 (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔))))
50		prcdnq 10409	. . . . . 6 ⊢ ((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) → (𝑥 <Q 𝑓 → 𝑥 ∈ 𝐴))
51	50	adantrd 494	. . . . 5 ⊢ ((𝐴 ∈ P ∧ 𝑓 ∈ 𝐴) → ((𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔)) → 𝑥 ∈ 𝐴))
52	51	rexlimdva 3284	. . . 4 ⊢ (𝐴 ∈ P → (∃𝑓 ∈ 𝐴 (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔)) → 𝑥 ∈ 𝐴))
53	49, 52	impbid 214	. . 3 ⊢ (𝐴 ∈ P → (𝑥 ∈ 𝐴 ↔ ∃𝑓 ∈ 𝐴 (𝑥 <Q 𝑓 ∧ ∃𝑔 𝑥 = (𝑓 ·Q 𝑔))))
54	19, 24, 53	3bitr4d 313	. 2 ⊢ (𝐴 ∈ P → (𝑥 ∈ (𝐴 ·P 1P) ↔ 𝑥 ∈ 𝐴))
55	54	eqrdv 2819	1 ⊢ (𝐴 ∈ P → (𝐴 ·P 1P) = 𝐴)

Syntax hints:   → wi 4   ↔ wb 208   ∧ wa 398   = wceq 1533  ∃wex 1776   ∈ wcel 2110  ∃wrex 3139   class class class wbr 5058  ‘cfv 6349  (class class class)co 7150  Qcnq 10268  1_Qc1q 10269   ·_Q cmq 10272  *_Qcrq 10273   <_Q cltq 10274  Pcnp 10275  1_Pc1p 10276   ·_P cmp 10278

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1792  ax-4 1806  ax-5 1907  ax-6 1966  ax-7 2011  ax-8 2112  ax-9 2120  ax-10 2141  ax-11 2157  ax-12 2173  ax-ext 2793  ax-sep 5195  ax-nul 5202  ax-pow 5258  ax-pr 5321  ax-un 7455  ax-inf2 9098

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3or 1084  df-3an 1085  df-tru 1536  df-ex 1777  df-nf 1781  df-sb 2066  df-mo 2618  df-eu 2650  df-clab 2800  df-cleq 2814  df-clel 2893  df-nfc 2963  df-ne 3017  df-ral 3143  df-rex 3144  df-reu 3145  df-rmo 3146  df-rab 3147  df-v 3496  df-sbc 3772  df-csb 3883  df-dif 3938  df-un 3940  df-in 3942  df-ss 3951  df-pss 3953  df-nul 4291  df-if 4467  df-pw 4540  df-sn 4561  df-pr 4563  df-tp 4565  df-op 4567  df-uni 4832  df-int 4869  df-iun 4913  df-br 5059  df-opab 5121  df-mpt 5139  df-tr 5165  df-id 5454  df-eprel 5459  df-po 5468  df-so 5469  df-fr 5508  df-we 5510  df-xp 5555  df-rel 5556  df-cnv 5557  df-co 5558  df-dm 5559  df-rn 5560  df-res 5561  df-ima 5562  df-pred 6142  df-ord 6188  df-on 6189  df-lim 6190  df-suc 6191  df-iota 6308  df-fun 6351  df-fn 6352  df-f 6353  df-f1 6354  df-fo 6355  df-f1o 6356  df-fv 6357  df-ov 7153  df-oprab 7154  df-mpo 7155  df-om 7575  df-1st 7683  df-2nd 7684  df-wrecs 7941  df-recs 8002  df-rdg 8040  df-1o 8096  df-oadd 8100  df-omul 8101  df-er 8283  df-ni 10288  df-pli 10289  df-mi 10290  df-lti 10291  df-plpq 10324  df-mpq 10325  df-ltpq 10326  df-enq 10327  df-nq 10328  df-erq 10329  df-plq 10330  df-mq 10331  df-1nq 10332  df-rq 10333  df-ltnq 10334  df-np 10397  df-1p 10398  df-mp 10400

This theorem is referenced by:  m1m1sr  10509  1idsr  10514