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Theorem ax1rid 10020
 Description: 1 is an identity element for real multiplication. Axiom 14 of 22 for real and complex numbers, derived from ZF set theory. Weakened from the original axiom in the form of statement in mulid1 10075, based on ideas by Eric Schmidt. This construction-dependent theorem should not be referenced directly; instead, use ax-1rid 10044. (Contributed by Scott Fenton, 3-Jan-2013.) (New usage is discouraged.)
Assertion
Ref Expression
ax1rid (𝐴 ∈ ℝ → (𝐴 · 1) = 𝐴)

Proof of Theorem ax1rid
Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 df-r 9984 . 2 ℝ = (R × {0R})
2 oveq1 6697 . . 3 (⟨𝑥, 𝑦⟩ = 𝐴 → (⟨𝑥, 𝑦⟩ · 1) = (𝐴 · 1))
3 id 22 . . 3 (⟨𝑥, 𝑦⟩ = 𝐴 → ⟨𝑥, 𝑦⟩ = 𝐴)
42, 3eqeq12d 2666 . 2 (⟨𝑥, 𝑦⟩ = 𝐴 → ((⟨𝑥, 𝑦⟩ · 1) = ⟨𝑥, 𝑦⟩ ↔ (𝐴 · 1) = 𝐴))
5 elsni 4227 . . 3 (𝑦 ∈ {0R} → 𝑦 = 0R)
6 df-1 9982 . . . . . . 7 1 = ⟨1R, 0R
76oveq2i 6701 . . . . . 6 (⟨𝑥, 0R⟩ · 1) = (⟨𝑥, 0R⟩ · ⟨1R, 0R⟩)
8 1sr 9940 . . . . . . . 8 1RR
9 mulresr 9998 . . . . . . . 8 ((𝑥R ∧ 1RR) → (⟨𝑥, 0R⟩ · ⟨1R, 0R⟩) = ⟨(𝑥 ·R 1R), 0R⟩)
108, 9mpan2 707 . . . . . . 7 (𝑥R → (⟨𝑥, 0R⟩ · ⟨1R, 0R⟩) = ⟨(𝑥 ·R 1R), 0R⟩)
11 1idsr 9957 . . . . . . . 8 (𝑥R → (𝑥 ·R 1R) = 𝑥)
1211opeq1d 4439 . . . . . . 7 (𝑥R → ⟨(𝑥 ·R 1R), 0R⟩ = ⟨𝑥, 0R⟩)
1310, 12eqtrd 2685 . . . . . 6 (𝑥R → (⟨𝑥, 0R⟩ · ⟨1R, 0R⟩) = ⟨𝑥, 0R⟩)
147, 13syl5eq 2697 . . . . 5 (𝑥R → (⟨𝑥, 0R⟩ · 1) = ⟨𝑥, 0R⟩)
15 opeq2 4434 . . . . . . 7 (𝑦 = 0R → ⟨𝑥, 𝑦⟩ = ⟨𝑥, 0R⟩)
1615oveq1d 6705 . . . . . 6 (𝑦 = 0R → (⟨𝑥, 𝑦⟩ · 1) = (⟨𝑥, 0R⟩ · 1))
1716, 15eqeq12d 2666 . . . . 5 (𝑦 = 0R → ((⟨𝑥, 𝑦⟩ · 1) = ⟨𝑥, 𝑦⟩ ↔ (⟨𝑥, 0R⟩ · 1) = ⟨𝑥, 0R⟩))
1814, 17syl5ibr 236 . . . 4 (𝑦 = 0R → (𝑥R → (⟨𝑥, 𝑦⟩ · 1) = ⟨𝑥, 𝑦⟩))
1918impcom 445 . . 3 ((𝑥R𝑦 = 0R) → (⟨𝑥, 𝑦⟩ · 1) = ⟨𝑥, 𝑦⟩)
205, 19sylan2 490 . 2 ((𝑥R𝑦 ∈ {0R}) → (⟨𝑥, 𝑦⟩ · 1) = ⟨𝑥, 𝑦⟩)
211, 4, 20optocl 5229 1 (𝐴 ∈ ℝ → (𝐴 · 1) = 𝐴)
 Colors of variables: wff setvar class Syntax hints:   → wi 4   = wceq 1523   ∈ wcel 2030  {csn 4210  ⟨cop 4216  (class class class)co 6690  Rcnr 9725  0Rc0r 9726  1Rc1r 9727   ·R cmr 9730  ℝcr 9973  1c1 9975   · cmul 9979 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1762  ax-4 1777  ax-5 1879  ax-6 1945  ax-7 1981  ax-8 2032  ax-9 2039  ax-10 2059  ax-11 2074  ax-12 2087  ax-13 2282  ax-ext 2631  ax-sep 4814  ax-nul 4822  ax-pow 4873  ax-pr 4936  ax-un 6991  ax-inf2 8576 This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-3or 1055  df-3an 1056  df-tru 1526  df-ex 1745  df-nf 1750  df-sb 1938  df-eu 2502  df-mo 2503  df-clab 2638  df-cleq 2644  df-clel 2647  df-nfc 2782  df-ne 2824  df-ral 2946  df-rex 2947  df-reu 2948  df-rmo 2949  df-rab 2950  df-v 3233  df-sbc 3469  df-csb 3567  df-dif 3610  df-un 3612  df-in 3614  df-ss 3621  df-pss 3623  df-nul 3949  df-if 4120  df-pw 4193  df-sn 4211  df-pr 4213  df-tp 4215  df-op 4217  df-uni 4469  df-int 4508  df-iun 4554  df-br 4686  df-opab 4746  df-mpt 4763  df-tr 4786  df-id 5053  df-eprel 5058  df-po 5064  df-so 5065  df-fr 5102  df-we 5104  df-xp 5149  df-rel 5150  df-cnv 5151  df-co 5152  df-dm 5153  df-rn 5154  df-res 5155  df-ima 5156  df-pred 5718  df-ord 5764  df-on 5765  df-lim 5766  df-suc 5767  df-iota 5889  df-fun 5928  df-fn 5929  df-f 5930  df-f1 5931  df-fo 5932  df-f1o 5933  df-fv 5934  df-ov 6693  df-oprab 6694  df-mpt2 6695  df-om 7108  df-1st 7210  df-2nd 7211  df-wrecs 7452  df-recs 7513  df-rdg 7551  df-1o 7605  df-oadd 7609  df-omul 7610  df-er 7787  df-ec 7789  df-qs 7793  df-ni 9732  df-pli 9733  df-mi 9734  df-lti 9735  df-plpq 9768  df-mpq 9769  df-ltpq 9770  df-enq 9771  df-nq 9772  df-erq 9773  df-plq 9774  df-mq 9775  df-1nq 9776  df-rq 9777  df-ltnq 9778  df-np 9841  df-1p 9842  df-plp 9843  df-mp 9844  df-ltp 9845  df-enr 9915  df-nr 9916  df-plr 9917  df-mr 9918  df-0r 9920  df-1r 9921  df-m1r 9922  df-c 9980  df-1 9982  df-r 9984  df-mul 9986 This theorem is referenced by: (None)
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