Theorem nn0gcdsq 16690

Description: Squaring commutes with GCD, in particular two coprime numbers have coprime squares. (Contributed by Stefan O'Rear, 15-Sep-2014.)

Assertion

Ref	Expression
nn0gcdsq	⊢ ((𝐴 ∈ ℕ0 ∧ 𝐵 ∈ ℕ0) → ((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)))

Proof of Theorem nn0gcdsq

Step	Hyp	Ref	Expression
1		elnn0 12476	. 2 ⊢ (𝐴 ∈ ℕ0 ↔ (𝐴 ∈ ℕ ∨ 𝐴 = 0))
2		elnn0 12476	. 2 ⊢ (𝐵 ∈ ℕ0 ↔ (𝐵 ∈ ℕ ∨ 𝐵 = 0))
3		sqgcd 16504	. . 3 ⊢ ((𝐴 ∈ ℕ ∧ 𝐵 ∈ ℕ) → ((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)))
4		nncn 12222	. . . . . . 7 ⊢ (𝐵 ∈ ℕ → 𝐵 ∈ ℂ)
5		abssq 15255	. . . . . . 7 ⊢ (𝐵 ∈ ℂ → ((abs‘𝐵)↑2) = (abs‘(𝐵↑2)))
6	4, 5	syl 17	. . . . . 6 ⊢ (𝐵 ∈ ℕ → ((abs‘𝐵)↑2) = (abs‘(𝐵↑2)))
7		nnz 12581	. . . . . . . 8 ⊢ (𝐵 ∈ ℕ → 𝐵 ∈ ℤ)
8		gcd0id 16462	. . . . . . . 8 ⊢ (𝐵 ∈ ℤ → (0 gcd 𝐵) = (abs‘𝐵))
9	7, 8	syl 17	. . . . . . 7 ⊢ (𝐵 ∈ ℕ → (0 gcd 𝐵) = (abs‘𝐵))
10	9	oveq1d 7426	. . . . . 6 ⊢ (𝐵 ∈ ℕ → ((0 gcd 𝐵)↑2) = ((abs‘𝐵)↑2))
11		sq0 14158	. . . . . . . . 9 ⊢ (0↑2) = 0
12	11	a1i 11	. . . . . . . 8 ⊢ (𝐵 ∈ ℕ → (0↑2) = 0)
13	12	oveq1d 7426	. . . . . . 7 ⊢ (𝐵 ∈ ℕ → ((0↑2) gcd (𝐵↑2)) = (0 gcd (𝐵↑2)))
14		zsqcl 14096	. . . . . . . 8 ⊢ (𝐵 ∈ ℤ → (𝐵↑2) ∈ ℤ)
15		gcd0id 16462	. . . . . . . 8 ⊢ ((𝐵↑2) ∈ ℤ → (0 gcd (𝐵↑2)) = (abs‘(𝐵↑2)))
16	7, 14, 15	3syl 18	. . . . . . 7 ⊢ (𝐵 ∈ ℕ → (0 gcd (𝐵↑2)) = (abs‘(𝐵↑2)))
17	13, 16	eqtrd 2772	. . . . . 6 ⊢ (𝐵 ∈ ℕ → ((0↑2) gcd (𝐵↑2)) = (abs‘(𝐵↑2)))
18	6, 10, 17	3eqtr4d 2782	. . . . 5 ⊢ (𝐵 ∈ ℕ → ((0 gcd 𝐵)↑2) = ((0↑2) gcd (𝐵↑2)))
19	18	adantl 482	. . . 4 ⊢ ((𝐴 = 0 ∧ 𝐵 ∈ ℕ) → ((0 gcd 𝐵)↑2) = ((0↑2) gcd (𝐵↑2)))
20		oveq1 7418	. . . . . . 7 ⊢ (𝐴 = 0 → (𝐴 gcd 𝐵) = (0 gcd 𝐵))
21	20	oveq1d 7426	. . . . . 6 ⊢ (𝐴 = 0 → ((𝐴 gcd 𝐵)↑2) = ((0 gcd 𝐵)↑2))
22		oveq1 7418	. . . . . . 7 ⊢ (𝐴 = 0 → (𝐴↑2) = (0↑2))
23	22	oveq1d 7426	. . . . . 6 ⊢ (𝐴 = 0 → ((𝐴↑2) gcd (𝐵↑2)) = ((0↑2) gcd (𝐵↑2)))
24	21, 23	eqeq12d 2748	. . . . 5 ⊢ (𝐴 = 0 → (((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)) ↔ ((0 gcd 𝐵)↑2) = ((0↑2) gcd (𝐵↑2))))
25	24	adantr 481	. . . 4 ⊢ ((𝐴 = 0 ∧ 𝐵 ∈ ℕ) → (((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)) ↔ ((0 gcd 𝐵)↑2) = ((0↑2) gcd (𝐵↑2))))
26	19, 25	mpbird 256	. . 3 ⊢ ((𝐴 = 0 ∧ 𝐵 ∈ ℕ) → ((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)))
27		nncn 12222	. . . . . . 7 ⊢ (𝐴 ∈ ℕ → 𝐴 ∈ ℂ)
28		abssq 15255	. . . . . . 7 ⊢ (𝐴 ∈ ℂ → ((abs‘𝐴)↑2) = (abs‘(𝐴↑2)))
29	27, 28	syl 17	. . . . . 6 ⊢ (𝐴 ∈ ℕ → ((abs‘𝐴)↑2) = (abs‘(𝐴↑2)))
30		nnz 12581	. . . . . . . 8 ⊢ (𝐴 ∈ ℕ → 𝐴 ∈ ℤ)
31		gcdid0 16463	. . . . . . . 8 ⊢ (𝐴 ∈ ℤ → (𝐴 gcd 0) = (abs‘𝐴))
32	30, 31	syl 17	. . . . . . 7 ⊢ (𝐴 ∈ ℕ → (𝐴 gcd 0) = (abs‘𝐴))
33	32	oveq1d 7426	. . . . . 6 ⊢ (𝐴 ∈ ℕ → ((𝐴 gcd 0)↑2) = ((abs‘𝐴)↑2))
34	11	a1i 11	. . . . . . . 8 ⊢ (𝐴 ∈ ℕ → (0↑2) = 0)
35	34	oveq2d 7427	. . . . . . 7 ⊢ (𝐴 ∈ ℕ → ((𝐴↑2) gcd (0↑2)) = ((𝐴↑2) gcd 0))
36		zsqcl 14096	. . . . . . . 8 ⊢ (𝐴 ∈ ℤ → (𝐴↑2) ∈ ℤ)
37		gcdid0 16463	. . . . . . . 8 ⊢ ((𝐴↑2) ∈ ℤ → ((𝐴↑2) gcd 0) = (abs‘(𝐴↑2)))
38	30, 36, 37	3syl 18	. . . . . . 7 ⊢ (𝐴 ∈ ℕ → ((𝐴↑2) gcd 0) = (abs‘(𝐴↑2)))
39	35, 38	eqtrd 2772	. . . . . 6 ⊢ (𝐴 ∈ ℕ → ((𝐴↑2) gcd (0↑2)) = (abs‘(𝐴↑2)))
40	29, 33, 39	3eqtr4d 2782	. . . . 5 ⊢ (𝐴 ∈ ℕ → ((𝐴 gcd 0)↑2) = ((𝐴↑2) gcd (0↑2)))
41	40	adantr 481	. . . 4 ⊢ ((𝐴 ∈ ℕ ∧ 𝐵 = 0) → ((𝐴 gcd 0)↑2) = ((𝐴↑2) gcd (0↑2)))
42		oveq2 7419	. . . . . . 7 ⊢ (𝐵 = 0 → (𝐴 gcd 𝐵) = (𝐴 gcd 0))
43	42	oveq1d 7426	. . . . . 6 ⊢ (𝐵 = 0 → ((𝐴 gcd 𝐵)↑2) = ((𝐴 gcd 0)↑2))
44		oveq1 7418	. . . . . . 7 ⊢ (𝐵 = 0 → (𝐵↑2) = (0↑2))
45	44	oveq2d 7427	. . . . . 6 ⊢ (𝐵 = 0 → ((𝐴↑2) gcd (𝐵↑2)) = ((𝐴↑2) gcd (0↑2)))
46	43, 45	eqeq12d 2748	. . . . 5 ⊢ (𝐵 = 0 → (((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)) ↔ ((𝐴 gcd 0)↑2) = ((𝐴↑2) gcd (0↑2))))
47	46	adantl 482	. . . 4 ⊢ ((𝐴 ∈ ℕ ∧ 𝐵 = 0) → (((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)) ↔ ((𝐴 gcd 0)↑2) = ((𝐴↑2) gcd (0↑2))))
48	41, 47	mpbird 256	. . 3 ⊢ ((𝐴 ∈ ℕ ∧ 𝐵 = 0) → ((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)))
49		gcd0val 16440	. . . . . 6 ⊢ (0 gcd 0) = 0
50	49	oveq1i 7421	. . . . 5 ⊢ ((0 gcd 0)↑2) = (0↑2)
51	11, 11	oveq12i 7423	. . . . . 6 ⊢ ((0↑2) gcd (0↑2)) = (0 gcd 0)
52	51, 49	eqtri 2760	. . . . 5 ⊢ ((0↑2) gcd (0↑2)) = 0
53	11, 50, 52	3eqtr4i 2770	. . . 4 ⊢ ((0 gcd 0)↑2) = ((0↑2) gcd (0↑2))
54		oveq12 7420	. . . . 5 ⊢ ((𝐴 = 0 ∧ 𝐵 = 0) → (𝐴 gcd 𝐵) = (0 gcd 0))
55	54	oveq1d 7426	. . . 4 ⊢ ((𝐴 = 0 ∧ 𝐵 = 0) → ((𝐴 gcd 𝐵)↑2) = ((0 gcd 0)↑2))
56	22, 44	oveqan12d 7430	. . . 4 ⊢ ((𝐴 = 0 ∧ 𝐵 = 0) → ((𝐴↑2) gcd (𝐵↑2)) = ((0↑2) gcd (0↑2)))
57	53, 55, 56	3eqtr4a 2798	. . 3 ⊢ ((𝐴 = 0 ∧ 𝐵 = 0) → ((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)))
58	3, 26, 48, 57	ccase 1036	. 2 ⊢ (((𝐴 ∈ ℕ ∨ 𝐴 = 0) ∧ (𝐵 ∈ ℕ ∨ 𝐵 = 0)) → ((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)))
59	1, 2, 58	syl2anb 598	1 ⊢ ((𝐴 ∈ ℕ0 ∧ 𝐵 ∈ ℕ0) → ((𝐴 gcd 𝐵)↑2) = ((𝐴↑2) gcd (𝐵↑2)))

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 396   ∨ wo 845   = wceq 1541   ∈ wcel 2106  ‘cfv 6543  (class class class)co 7411  ℂcc 11110  0cc0 11112  ℕcn 12214  2c2 12269  ℕ₀cn0 12474  ℤcz 12560  ↑cexp 14029  abscabs 15183   gcd cgcd 16437

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2703  ax-sep 5299  ax-nul 5306  ax-pow 5363  ax-pr 5427  ax-un 7727  ax-cnex 11168  ax-resscn 11169  ax-1cn 11170  ax-icn 11171  ax-addcl 11172  ax-addrcl 11173  ax-mulcl 11174  ax-mulrcl 11175  ax-mulcom 11176  ax-addass 11177  ax-mulass 11178  ax-distr 11179  ax-i2m1 11180  ax-1ne0 11181  ax-1rid 11182  ax-rnegex 11183  ax-rrecex 11184  ax-cnre 11185  ax-pre-lttri 11186  ax-pre-lttrn 11187  ax-pre-ltadd 11188  ax-pre-mulgt0 11189  ax-pre-sup 11190

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-3or 1088  df-3an 1089  df-tru 1544  df-fal 1554  df-ex 1782  df-nf 1786  df-sb 2068  df-mo 2534  df-eu 2563  df-clab 2710  df-cleq 2724  df-clel 2810  df-nfc 2885  df-ne 2941  df-nel 3047  df-ral 3062  df-rex 3071  df-rmo 3376  df-reu 3377  df-rab 3433  df-v 3476  df-sbc 3778  df-csb 3894  df-dif 3951  df-un 3953  df-in 3955  df-ss 3965  df-pss 3967  df-nul 4323  df-if 4529  df-pw 4604  df-sn 4629  df-pr 4631  df-op 4635  df-uni 4909  df-iun 4999  df-br 5149  df-opab 5211  df-mpt 5232  df-tr 5266  df-id 5574  df-eprel 5580  df-po 5588  df-so 5589  df-fr 5631  df-we 5633  df-xp 5682  df-rel 5683  df-cnv 5684  df-co 5685  df-dm 5686  df-rn 5687  df-res 5688  df-ima 5689  df-pred 6300  df-ord 6367  df-on 6368  df-lim 6369  df-suc 6370  df-iota 6495  df-fun 6545  df-fn 6546  df-f 6547  df-f1 6548  df-fo 6549  df-f1o 6550  df-fv 6551  df-riota 7367  df-ov 7414  df-oprab 7415  df-mpo 7416  df-om 7858  df-2nd 7978  df-frecs 8268  df-wrecs 8299  df-recs 8373  df-rdg 8412  df-er 8705  df-en 8942  df-dom 8943  df-sdom 8944  df-sup 9439  df-inf 9440  df-pnf 11252  df-mnf 11253  df-xr 11254  df-ltxr 11255  df-le 11256  df-sub 11448  df-neg 11449  df-div 11874  df-nn 12215  df-2 12277  df-3 12278  df-n0 12475  df-z 12561  df-uz 12825  df-rp 12977  df-fl 13759  df-mod 13837  df-seq 13969  df-exp 14030  df-cj 15048  df-re 15049  df-im 15050  df-sqrt 15184  df-abs 15185  df-dvds 16200  df-gcd 16438

This theorem is referenced by:  zgcdsq  16691