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Theorem sqrt2irrap 12754
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 12736. (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 9856 . . 3 (𝑄 ∈ ℚ ↔ ∃𝑎 ∈ ℤ ∃𝑏 ∈ ℕ 𝑄 = (𝑎 / 𝑏))
21biimpi 120 . 2 (𝑄 ∈ ℚ → ∃𝑎 ∈ ℤ ∃𝑏 ∈ ℕ 𝑄 = (𝑎 / 𝑏))
3 simplrl 537 . . . . . . . . 9 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → 𝑎 ∈ ℤ)
43adantr 276 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑎 ∈ ℤ)
5 simplrr 538 . . . . . . . . 9 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → 𝑏 ∈ ℕ)
65adantr 276 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑏 ∈ ℕ)
7 znq 9858 . . . . . . . . 9 ((𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ) → (𝑎 / 𝑏) ∈ ℚ)
8 qre 9859 . . . . . . . . 9 ((𝑎 / 𝑏) ∈ ℚ → (𝑎 / 𝑏) ∈ ℝ)
97, 8syl 14 . . . . . . . 8 ((𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ) → (𝑎 / 𝑏) ∈ ℝ)
104, 6, 9syl2anc 411 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 / 𝑏) ∈ ℝ)
11 sqrt2re 12737 . . . . . . . 8 (√‘2) ∈ ℝ
1211a1i 9 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (√‘2) ∈ ℝ)
13 0red 8180 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 0 ∈ ℝ)
144zcnd 9603 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑎 ∈ ℂ)
156nncnd 9157 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑏 ∈ ℂ)
166nnap0d 9189 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑏 # 0)
1714, 15, 16divrecapd 8973 . . . . . . . . 9 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 / 𝑏) = (𝑎 · (1 / 𝑏)))
184zred 9602 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑎 ∈ ℝ)
196nnrecred 9190 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (1 / 𝑏) ∈ ℝ)
20 simpr 110 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑎 ≤ 0)
21 1red 8194 . . . . . . . . . . 11 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 1 ∈ ℝ)
226nnrpd 9929 . . . . . . . . . . 11 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 𝑏 ∈ ℝ+)
23 0le1 8661 . . . . . . . . . . . 12 0 ≤ 1
2423a1i 9 . . . . . . . . . . 11 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 0 ≤ 1)
2521, 22, 24divge0d 9972 . . . . . . . . . 10 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 0 ≤ (1 / 𝑏))
26 mulle0r 9124 . . . . . . . . . 10 (((𝑎 ∈ ℝ ∧ (1 / 𝑏) ∈ ℝ) ∧ (𝑎 ≤ 0 ∧ 0 ≤ (1 / 𝑏))) → (𝑎 · (1 / 𝑏)) ≤ 0)
2718, 19, 20, 25, 26syl22anc 1274 . . . . . . . . 9 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 · (1 / 𝑏)) ≤ 0)
2817, 27eqbrtrd 4110 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 / 𝑏) ≤ 0)
29 2re 9213 . . . . . . . . . 10 2 ∈ ℝ
30 2pos 9234 . . . . . . . . . 10 0 < 2
3129, 30sqrtgt0ii 11693 . . . . . . . . 9 0 < (√‘2)
3231a1i 9 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → 0 < (√‘2))
3310, 13, 12, 28, 32lelttrd 8304 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (𝑎 / 𝑏) < (√‘2))
3410, 12, 33gtapd 8817 . . . . . 6 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 𝑎 ≤ 0) → (√‘2) # (𝑎 / 𝑏))
353adantr 276 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → 𝑎 ∈ ℤ)
36 simpr 110 . . . . . . . 8 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → 0 < 𝑎)
37 elnnz 9489 . . . . . . . 8 (𝑎 ∈ ℕ ↔ (𝑎 ∈ ℤ ∧ 0 < 𝑎))
3835, 36, 37sylanbrc 417 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → 𝑎 ∈ ℕ)
395adantr 276 . . . . . . 7 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → 𝑏 ∈ ℕ)
40 sqrt2irraplemnn 12753 . . . . . . 7 ((𝑎 ∈ ℕ ∧ 𝑏 ∈ ℕ) → (√‘2) # (𝑎 / 𝑏))
4138, 39, 40syl2anc 411 . . . . . 6 ((((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) ∧ 0 < 𝑎) → (√‘2) # (𝑎 / 𝑏))
42 0z 9490 . . . . . . . . 9 0 ∈ ℤ
43 zlelttric 9524 . . . . . . . . 9 ((𝑎 ∈ ℤ ∧ 0 ∈ ℤ) → (𝑎 ≤ 0 ∨ 0 < 𝑎))
4442, 43mpan2 425 . . . . . . . 8 (𝑎 ∈ ℤ → (𝑎 ≤ 0 ∨ 0 < 𝑎))
4544ad2antrl 490 . . . . . . 7 ((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) → (𝑎 ≤ 0 ∨ 0 < 𝑎))
4645adantr 276 . . . . . 6 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → (𝑎 ≤ 0 ∨ 0 < 𝑎))
4734, 41, 46mpjaodan 805 . . . . 5 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → (√‘2) # (𝑎 / 𝑏))
48 simpr 110 . . . . 5 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → 𝑄 = (𝑎 / 𝑏))
4947, 48breqtrrd 4116 . . . 4 (((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) ∧ 𝑄 = (𝑎 / 𝑏)) → (√‘2) # 𝑄)
5049ex 115 . . 3 ((𝑄 ∈ ℚ ∧ (𝑎 ∈ ℤ ∧ 𝑏 ∈ ℕ)) → (𝑄 = (𝑎 / 𝑏) → (√‘2) # 𝑄))
5150rexlimdvva 2658 . 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 104  wo 715   = wceq 1397  wcel 2202  wrex 2511   class class class wbr 4088  cfv 5326  (class class class)co 6018  cr 8031  0cc0 8032  1c1 8033   · cmul 8037   < clt 8214  cle 8215   # cap 8761   / cdiv 8852  cn 9143  2c2 9194  cz 9479  cq 9853  csqrt 11558
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-13 2204  ax-14 2205  ax-ext 2213  ax-coll 4204  ax-sep 4207  ax-nul 4215  ax-pow 4264  ax-pr 4299  ax-un 4530  ax-setind 4635  ax-iinf 4686  ax-cnex 8123  ax-resscn 8124  ax-1cn 8125  ax-1re 8126  ax-icn 8127  ax-addcl 8128  ax-addrcl 8129  ax-mulcl 8130  ax-mulrcl 8131  ax-addcom 8132  ax-mulcom 8133  ax-addass 8134  ax-mulass 8135  ax-distr 8136  ax-i2m1 8137  ax-0lt1 8138  ax-1rid 8139  ax-0id 8140  ax-rnegex 8141  ax-precex 8142  ax-cnre 8143  ax-pre-ltirr 8144  ax-pre-ltwlin 8145  ax-pre-lttrn 8146  ax-pre-apti 8147  ax-pre-ltadd 8148  ax-pre-mulgt0 8149  ax-pre-mulext 8150  ax-arch 8151  ax-caucvg 8152
This theorem depends on definitions:  df-bi 117  df-stab 838  df-dc 842  df-3or 1005  df-3an 1006  df-tru 1400  df-fal 1403  df-xor 1420  df-nf 1509  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ne 2403  df-nel 2498  df-ral 2515  df-rex 2516  df-reu 2517  df-rmo 2518  df-rab 2519  df-v 2804  df-sbc 3032  df-csb 3128  df-dif 3202  df-un 3204  df-in 3206  df-ss 3213  df-nul 3495  df-if 3606  df-pw 3654  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-int 3929  df-iun 3972  df-br 4089  df-opab 4151  df-mpt 4152  df-tr 4188  df-id 4390  df-po 4393  df-iso 4394  df-iord 4463  df-on 4465  df-ilim 4466  df-suc 4468  df-iom 4689  df-xp 4731  df-rel 4732  df-cnv 4733  df-co 4734  df-dm 4735  df-rn 4736  df-res 4737  df-ima 4738  df-iota 5286  df-fun 5328  df-fn 5329  df-f 5330  df-f1 5331  df-fo 5332  df-f1o 5333  df-fv 5334  df-riota 5971  df-ov 6021  df-oprab 6022  df-mpo 6023  df-1st 6303  df-2nd 6304  df-recs 6471  df-frec 6557  df-1o 6582  df-2o 6583  df-er 6702  df-en 6910  df-sup 7183  df-pnf 8216  df-mnf 8217  df-xr 8218  df-ltxr 8219  df-le 8220  df-sub 8352  df-neg 8353  df-reap 8755  df-ap 8762  df-div 8853  df-inn 9144  df-2 9202  df-3 9203  df-4 9204  df-n0 9403  df-z 9480  df-uz 9756  df-q 9854  df-rp 9889  df-fz 10244  df-fzo 10378  df-fl 10531  df-mod 10586  df-seqfrec 10711  df-exp 10802  df-cj 11404  df-re 11405  df-im 11406  df-rsqrt 11560  df-abs 11561  df-dvds 12351  df-gcd 12527  df-prm 12682
This theorem is referenced by:  2irrexpqap  15705
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