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Theorem ax1rid 9942
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 9997, based on ideas by Eric Schmidt. This construction-dependent theorem should not be referenced directly; instead, use ax-1rid 9966. (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 9906 . 2 ℝ = (R × {0R})
2 oveq1 6622 . . 3 (⟨𝑥, 𝑦⟩ = 𝐴 → (⟨𝑥, 𝑦⟩ · 1) = (𝐴 · 1))
3 id 22 . . 3 (⟨𝑥, 𝑦⟩ = 𝐴 → ⟨𝑥, 𝑦⟩ = 𝐴)
42, 3eqeq12d 2636 . 2 (⟨𝑥, 𝑦⟩ = 𝐴 → ((⟨𝑥, 𝑦⟩ · 1) = ⟨𝑥, 𝑦⟩ ↔ (𝐴 · 1) = 𝐴))
5 elsni 4172 . . 3 (𝑦 ∈ {0R} → 𝑦 = 0R)
6 df-1 9904 . . . . . . 7 1 = ⟨1R, 0R
76oveq2i 6626 . . . . . 6 (⟨𝑥, 0R⟩ · 1) = (⟨𝑥, 0R⟩ · ⟨1R, 0R⟩)
8 1sr 9862 . . . . . . . 8 1RR
9 mulresr 9920 . . . . . . . 8 ((𝑥R ∧ 1RR) → (⟨𝑥, 0R⟩ · ⟨1R, 0R⟩) = ⟨(𝑥 ·R 1R), 0R⟩)
108, 9mpan2 706 . . . . . . 7 (𝑥R → (⟨𝑥, 0R⟩ · ⟨1R, 0R⟩) = ⟨(𝑥 ·R 1R), 0R⟩)
11 1idsr 9879 . . . . . . . 8 (𝑥R → (𝑥 ·R 1R) = 𝑥)
1211opeq1d 4383 . . . . . . 7 (𝑥R → ⟨(𝑥 ·R 1R), 0R⟩ = ⟨𝑥, 0R⟩)
1310, 12eqtrd 2655 . . . . . 6 (𝑥R → (⟨𝑥, 0R⟩ · ⟨1R, 0R⟩) = ⟨𝑥, 0R⟩)
147, 13syl5eq 2667 . . . . 5 (𝑥R → (⟨𝑥, 0R⟩ · 1) = ⟨𝑥, 0R⟩)
15 opeq2 4378 . . . . . . 7 (𝑦 = 0R → ⟨𝑥, 𝑦⟩ = ⟨𝑥, 0R⟩)
1615oveq1d 6630 . . . . . 6 (𝑦 = 0R → (⟨𝑥, 𝑦⟩ · 1) = (⟨𝑥, 0R⟩ · 1))
1716, 15eqeq12d 2636 . . . . 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 446 . . 3 ((𝑥R𝑦 = 0R) → (⟨𝑥, 𝑦⟩ · 1) = ⟨𝑥, 𝑦⟩)
205, 19sylan2 491 . 2 ((𝑥R𝑦 ∈ {0R}) → (⟨𝑥, 𝑦⟩ · 1) = ⟨𝑥, 𝑦⟩)
211, 4, 20optocl 5166 1 (𝐴 ∈ ℝ → (𝐴 · 1) = 𝐴)
Colors of variables: wff setvar class
Syntax hints:  wi 4   = wceq 1480  wcel 1987  {csn 4155  cop 4161  (class class class)co 6615  Rcnr 9647  0Rc0r 9648  1Rc1r 9649   ·R cmr 9652  cr 9895  1c1 9897   · cmul 9901
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1719  ax-4 1734  ax-5 1836  ax-6 1885  ax-7 1932  ax-8 1989  ax-9 1996  ax-10 2016  ax-11 2031  ax-12 2044  ax-13 2245  ax-ext 2601  ax-sep 4751  ax-nul 4759  ax-pow 4813  ax-pr 4877  ax-un 6914  ax-inf2 8498
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1037  df-3an 1038  df-tru 1483  df-ex 1702  df-nf 1707  df-sb 1878  df-eu 2473  df-mo 2474  df-clab 2608  df-cleq 2614  df-clel 2617  df-nfc 2750  df-ne 2791  df-ral 2913  df-rex 2914  df-reu 2915  df-rmo 2916  df-rab 2917  df-v 3192  df-sbc 3423  df-csb 3520  df-dif 3563  df-un 3565  df-in 3567  df-ss 3574  df-pss 3576  df-nul 3898  df-if 4065  df-pw 4138  df-sn 4156  df-pr 4158  df-tp 4160  df-op 4162  df-uni 4410  df-int 4448  df-iun 4494  df-br 4624  df-opab 4684  df-mpt 4685  df-tr 4723  df-eprel 4995  df-id 4999  df-po 5005  df-so 5006  df-fr 5043  df-we 5045  df-xp 5090  df-rel 5091  df-cnv 5092  df-co 5093  df-dm 5094  df-rn 5095  df-res 5096  df-ima 5097  df-pred 5649  df-ord 5695  df-on 5696  df-lim 5697  df-suc 5698  df-iota 5820  df-fun 5859  df-fn 5860  df-f 5861  df-f1 5862  df-fo 5863  df-f1o 5864  df-fv 5865  df-ov 6618  df-oprab 6619  df-mpt2 6620  df-om 7028  df-1st 7128  df-2nd 7129  df-wrecs 7367  df-recs 7428  df-rdg 7466  df-1o 7520  df-oadd 7524  df-omul 7525  df-er 7702  df-ec 7704  df-qs 7708  df-ni 9654  df-pli 9655  df-mi 9656  df-lti 9657  df-plpq 9690  df-mpq 9691  df-ltpq 9692  df-enq 9693  df-nq 9694  df-erq 9695  df-plq 9696  df-mq 9697  df-1nq 9698  df-rq 9699  df-ltnq 9700  df-np 9763  df-1p 9764  df-plp 9765  df-mp 9766  df-ltp 9767  df-enr 9837  df-nr 9838  df-plr 9839  df-mr 9840  df-0r 9842  df-1r 9843  df-m1r 9844  df-c 9902  df-1 9904  df-r 9906  df-mul 9908
This theorem is referenced by: (None)
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