ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  sqrt2irrap GIF version

Theorem sqrt2irrap 12134
Description: The square root of 2 is irrational. That is, for any rational number, (√‘2) is apart from it. In the absence of excluded middle, we can distinguish between this and "the square root of 2 is not rational" which is sqrt2irr 12116. (Contributed by Jim Kingdon, 2-Oct-2021.)
Assertion
Ref Expression
sqrt2irrap (𝑄 ∈ ℚ → (√‘2) # 𝑄)

Proof of Theorem sqrt2irrap
Dummy variables 𝑎 𝑏 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 elq 9581 . . 3 (𝑄 ∈ ℚ ↔ ∃𝑎 ∈ ℤ ∃𝑏 ∈ ℕ 𝑄 = (𝑎 / 𝑏))
21biimpi 119 . 2 (𝑄 ∈ ℚ → ∃𝑎 ∈ ℤ ∃𝑏 ∈ ℕ 𝑄 = (𝑎 / 𝑏))
3 simplrl 530 . . . . . . . . 9 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → 𝑎 ∈ ℤ)
43adantr 274 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑎 ∈ ℤ)
5 simplrr 531 . . . . . . . . 9 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → 𝑏 ∈ ℕ)
65adantr 274 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑏 ∈ ℕ)
7 znq 9583 . . . . . . . . 9 ((𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ) → (𝑎 / 𝑏) ∈ ℚ)
8 qre 9584 . . . . . . . . 9 ((𝑎 / 𝑏) ∈ ℚ → (𝑎 / 𝑏) ∈ ℝ)
97, 8syl 14 . . . . . . . 8 ((𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ) → (𝑎 / 𝑏) ∈ ℝ)
104, 6, 9syl2anc 409 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 / 𝑏) ∈ ℝ)
11 sqrt2re 12117 . . . . . . . 8 (√‘2) ∈ ℝ
1211a1i 9 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (√‘2) ∈ ℝ)
13 0red 7921 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 0 ∈ ℝ)
144zcnd 9335 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑎 ∈ ℂ)
156nncnd 8892 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑏 ∈ ℂ)
166nnap0d 8924 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑏 # 0)
1714, 15, 16divrecapd 8710 . . . . . . . . 9 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 / 𝑏) = (𝑎 · (1 / 𝑏)))
184zred 9334 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑎 ∈ ℝ)
196nnrecred 8925 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (1 / 𝑏) ∈ ℝ)
20 simpr 109 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑎 ≤ 0)
21 1red 7935 . . . . . . . . . . 11 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 1 ∈ ℝ)
226nnrpd 9651 . . . . . . . . . . 11 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑏 ∈ ℝ+)
23 0le1 8400 . . . . . . . . . . . 12 0 ≤ 1
2423a1i 9 . . . . . . . . . . 11 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 0 ≤ 1)
2521, 22, 24divge0d 9694 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 0 ≤ (1 / 𝑏))
26 mulle0r 8860 . . . . . . . . . 10 (((𝑎 ∈ ℝ ∧ (1 / 𝑏) ∈ ℝ) ∧ (𝑎 ≤ 0 ∧ 0 ≤ (1 / 𝑏))) → (𝑎 · (1 / 𝑏)) ≤ 0)
2718, 19, 20, 25, 26syl22anc 1234 . . . . . . . . 9 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 · (1 / 𝑏)) ≤ 0)
2817, 27eqbrtrd 4011 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 / 𝑏) ≤ 0)
29 2re 8948 . . . . . . . . . 10 2 ∈ ℝ
30 2pos 8969 . . . . . . . . . 10 0 < 2
3129, 30sqrtgt0ii 11095 . . . . . . . . 9 0 < (√‘2)
3231a1i 9 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 0 < (√‘2))
3310, 13, 12, 28, 32lelttrd 8044 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 / 𝑏) < (√‘2))
3410, 12, 33gtapd 8556 . . . . . 6 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (√‘2) # (𝑎 / 𝑏))
353adantr 274 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → 𝑎 ∈ ℤ)
36 simpr 109 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → 0 < 𝑎)
37 elnnz 9222 . . . . . . . 8 (𝑎 ∈ ℕ ↔ (𝑎 ∈ ℤ ∧ 0 < 𝑎))
3835, 36, 37sylanbrc 415 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → 𝑎 ∈ ℕ)
395adantr 274 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → 𝑏 ∈ ℕ)
40 sqrt2irraplemnn 12133 . . . . . . 7 ((𝑎 ∈ ℕ ∧ 𝑏 ∈ ℕ) → (√‘2) # (𝑎 / 𝑏))
4138, 39, 40syl2anc 409 . . . . . 6 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → (√‘2) # (𝑎 / 𝑏))
42 0z 9223 . . . . . . . . 9 0 ∈ ℤ
43 zlelttric 9257 . . . . . . . . 9 ((𝑎 ∈ ℤ ∧ 0 ∈ ℤ) → (𝑎 ≤ 0 ∨ 0 < 𝑎))
4442, 43mpan2 423 . . . . . . . 8 (𝑎 ∈ ℤ → (𝑎 ≤ 0 ∨ 0 < 𝑎))
4544ad2antrl 487 . . . . . . 7 ((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) → (𝑎 ≤ 0 ∨ 0 < 𝑎))
4645adantr 274 . . . . . 6 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → (𝑎 ≤ 0 ∨ 0 < 𝑎))
4734, 41, 46mpjaodan 793 . . . . 5 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → (√‘2) # (𝑎 / 𝑏))
48 simpr 109 . . . . 5 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → 𝑄 = (𝑎 / 𝑏))
4947, 48breqtrrd 4017 . . . 4 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → (√‘2) # 𝑄)
5049ex 114 . . 3 ((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) → (𝑄 = (𝑎 / 𝑏) → (√‘2) # 𝑄))
5150rexlimdvva 2595 . 2 (𝑄 ∈ ℚ → (∃𝑎 ∈ ℤ ∃𝑏 ∈ ℕ 𝑄 = (𝑎 / 𝑏) → (√‘2) # 𝑄))
522, 51mpd 13 1 (𝑄 ∈ ℚ → (√‘2) # 𝑄)
Colors of variables: wff set class
Syntax hints:  wi 4  wa 103  wo 703   = wceq 1348  wcel 2141  wrex 2449   class class class wbr 3989  cfv 5198  (class class class)co 5853  cr 7773  0cc0 7774  1c1 7775   · cmul 7779   < clt 7954  cle 7955   # cap 8500   / cdiv 8589  cn 8878  2c2 8929  cz 9212  cq 9578  csqrt 10960
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 609  ax-in2 610  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-13 2143  ax-14 2144  ax-ext 2152  ax-coll 4104  ax-sep 4107  ax-nul 4115  ax-pow 4160  ax-pr 4194  ax-un 4418  ax-setind 4521  ax-iinf 4572  ax-cnex 7865  ax-resscn 7866  ax-1cn 7867  ax-1re 7868  ax-icn 7869  ax-addcl 7870  ax-addrcl 7871  ax-mulcl 7872  ax-mulrcl 7873  ax-addcom 7874  ax-mulcom 7875  ax-addass 7876  ax-mulass 7877  ax-distr 7878  ax-i2m1 7879  ax-0lt1 7880  ax-1rid 7881  ax-0id 7882  ax-rnegex 7883  ax-precex 7884  ax-cnre 7885  ax-pre-ltirr 7886  ax-pre-ltwlin 7887  ax-pre-lttrn 7888  ax-pre-apti 7889  ax-pre-ltadd 7890  ax-pre-mulgt0 7891  ax-pre-mulext 7892  ax-arch 7893  ax-caucvg 7894
This theorem depends on definitions:  df-bi 116  df-stab 826  df-dc 830  df-3or 974  df-3an 975  df-tru 1351  df-fal 1354  df-xor 1371  df-nf 1454  df-sb 1756  df-eu 2022  df-mo 2023  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-ne 2341  df-nel 2436  df-ral 2453  df-rex 2454  df-reu 2455  df-rmo 2456  df-rab 2457  df-v 2732  df-sbc 2956  df-csb 3050  df-dif 3123  df-un 3125  df-in 3127  df-ss 3134  df-nul 3415  df-if 3527  df-pw 3568  df-sn 3589  df-pr 3590  df-op 3592  df-uni 3797  df-int 3832  df-iun 3875  df-br 3990  df-opab 4051  df-mpt 4052  df-tr 4088  df-id 4278  df-po 4281  df-iso 4282  df-iord 4351  df-on 4353  df-ilim 4354  df-suc 4356  df-iom 4575  df-xp 4617  df-rel 4618  df-cnv 4619  df-co 4620  df-dm 4621  df-rn 4622  df-res 4623  df-ima 4624  df-iota 5160  df-fun 5200  df-fn 5201  df-f 5202  df-f1 5203  df-fo 5204  df-f1o 5205  df-fv 5206  df-riota 5809  df-ov 5856  df-oprab 5857  df-mpo 5858  df-1st 6119  df-2nd 6120  df-recs 6284  df-frec 6370  df-1o 6395  df-2o 6396  df-er 6513  df-en 6719  df-sup 6961  df-pnf 7956  df-mnf 7957  df-xr 7958  df-ltxr 7959  df-le 7960  df-sub 8092  df-neg 8093  df-reap 8494  df-ap 8501  df-div 8590  df-inn 8879  df-2 8937  df-3 8938  df-4 8939  df-n0 9136  df-z 9213  df-uz 9488  df-q 9579  df-rp 9611  df-fz 9966  df-fzo 10099  df-fl 10226  df-mod 10279  df-seqfrec 10402  df-exp 10476  df-cj 10806  df-re 10807  df-im 10808  df-rsqrt 10962  df-abs 10963  df-dvds 11750  df-gcd 11898  df-prm 12062
This theorem is referenced by:  2irrexpqap  13690
  Copyright terms: Public domain W3C validator