lcmgcdeq - Metamath Proof Explorer

	Metamath Proof Explorer		< Previous Next > Nearby theorems
Mirrors > Home > MPE Home > Th. List > lcmgcdeq		Structured version Visualization version GIF version

Theorem lcmgcdeq 16659

Description: Two integers' absolute values are equal iff their least common multiple and greatest common divisor are equal. (Contributed by Steve Rodriguez, 20-Jan-2020.)

**Assertion**
Ref	Expression
lcmgcdeq	⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 lcm 𝑁) = (𝑀 gcd 𝑁) ↔ (abs‘𝑀) = (abs‘𝑁)))

**Proof of Theorem lcmgcdeq**
Step	Hyp	Ref	Expression
1		dvdslcm 16645	. . . . . . 7 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ (𝑀 lcm 𝑁) ∧ 𝑁 ∥ (𝑀 lcm 𝑁)))
2	1	simpld 494	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → 𝑀 ∥ (𝑀 lcm 𝑁))
3	2	adantr 480	. . . . 5 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → 𝑀 ∥ (𝑀 lcm 𝑁))
4		gcddvds 16549	. . . . . . . 8 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 gcd 𝑁) ∥ 𝑀 ∧ (𝑀 gcd 𝑁) ∥ 𝑁))
5	4	simprd 495	. . . . . . 7 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 gcd 𝑁) ∥ 𝑁)
6		breq1 5169	. . . . . . 7 ⊢ ((𝑀 lcm 𝑁) = (𝑀 gcd 𝑁) → ((𝑀 lcm 𝑁) ∥ 𝑁 ↔ (𝑀 gcd 𝑁) ∥ 𝑁))
7	5, 6	syl5ibrcom 247	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 lcm 𝑁) = (𝑀 gcd 𝑁) → (𝑀 lcm 𝑁) ∥ 𝑁))
8	7	imp 406	. . . . 5 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → (𝑀 lcm 𝑁) ∥ 𝑁)
9		lcmcl 16648	. . . . . . . . . . 11 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 lcm 𝑁) ∈ ℕ₀)
10	9	nn0zd 12665	. . . . . . . . . 10 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 lcm 𝑁) ∈ ℤ)
11		dvdstr 16342	. . . . . . . . . 10 ⊢ ((𝑀 ∈ ℤ ∧ (𝑀 lcm 𝑁) ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑁) → 𝑀 ∥ 𝑁))
12	10, 11	syl3an2 1164	. . . . . . . . 9 ⊢ ((𝑀 ∈ ℤ ∧ (𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ 𝑁 ∈ ℤ) → ((𝑀 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑁) → 𝑀 ∥ 𝑁))
13	12	3com12 1123	. . . . . . . 8 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ 𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑁) → 𝑀 ∥ 𝑁))
14	13	3expb 1120	. . . . . . 7 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ)) → ((𝑀 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑁) → 𝑀 ∥ 𝑁))
15	14	anidms 566	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑁) → 𝑀 ∥ 𝑁))
16	15	adantr 480	. . . . 5 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → ((𝑀 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑁) → 𝑀 ∥ 𝑁))
17	3, 8, 16	mp2and 698	. . . 4 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → 𝑀 ∥ 𝑁)
18		absdvdsb 16323	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (abs‘𝑀) ∥ 𝑁))
19		zabscl 15362	. . . . . . 7 ⊢ (𝑀 ∈ ℤ → (abs‘𝑀) ∈ ℤ)
20		dvdsabsb 16324	. . . . . . 7 ⊢ (((abs‘𝑀) ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((abs‘𝑀) ∥ 𝑁 ↔ (abs‘𝑀) ∥ (abs‘𝑁)))
21	19, 20	sylan 579	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((abs‘𝑀) ∥ 𝑁 ↔ (abs‘𝑀) ∥ (abs‘𝑁)))
22	18, 21	bitrd 279	. . . . 5 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 ∥ 𝑁 ↔ (abs‘𝑀) ∥ (abs‘𝑁)))
23	22	adantr 480	. . . 4 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → (𝑀 ∥ 𝑁 ↔ (abs‘𝑀) ∥ (abs‘𝑁)))
24	17, 23	mpbid 232	. . 3 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → (abs‘𝑀) ∥ (abs‘𝑁))
25	1	simprd 495	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → 𝑁 ∥ (𝑀 lcm 𝑁))
26	25	adantr 480	. . . . 5 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → 𝑁 ∥ (𝑀 lcm 𝑁))
27	4	simpld 494	. . . . . . 7 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀 gcd 𝑁) ∥ 𝑀)
28		breq1 5169	. . . . . . 7 ⊢ ((𝑀 lcm 𝑁) = (𝑀 gcd 𝑁) → ((𝑀 lcm 𝑁) ∥ 𝑀 ↔ (𝑀 gcd 𝑁) ∥ 𝑀))
29	27, 28	syl5ibrcom 247	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 lcm 𝑁) = (𝑀 gcd 𝑁) → (𝑀 lcm 𝑁) ∥ 𝑀))
30	29	imp 406	. . . . 5 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → (𝑀 lcm 𝑁) ∥ 𝑀)
31		dvdstr 16342	. . . . . . . . . 10 ⊢ ((𝑁 ∈ ℤ ∧ (𝑀 lcm 𝑁) ∈ ℤ ∧ 𝑀 ∈ ℤ) → ((𝑁 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑀) → 𝑁 ∥ 𝑀))
32	10, 31	syl3an2 1164	. . . . . . . . 9 ⊢ ((𝑁 ∈ ℤ ∧ (𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ 𝑀 ∈ ℤ) → ((𝑁 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑀) → 𝑁 ∥ 𝑀))
33	32	3coml 1127	. . . . . . . 8 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ 𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑁 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑀) → 𝑁 ∥ 𝑀))
34	33	3expb 1120	. . . . . . 7 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ)) → ((𝑁 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑀) → 𝑁 ∥ 𝑀))
35	34	anidms 566	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑁 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑀) → 𝑁 ∥ 𝑀))
36	35	adantr 480	. . . . 5 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → ((𝑁 ∥ (𝑀 lcm 𝑁) ∧ (𝑀 lcm 𝑁) ∥ 𝑀) → 𝑁 ∥ 𝑀))
37	26, 30, 36	mp2and 698	. . . 4 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → 𝑁 ∥ 𝑀)
38		absdvdsb 16323	. . . . . . 7 ⊢ ((𝑁 ∈ ℤ ∧ 𝑀 ∈ ℤ) → (𝑁 ∥ 𝑀 ↔ (abs‘𝑁) ∥ 𝑀))
39		zabscl 15362	. . . . . . . 8 ⊢ (𝑁 ∈ ℤ → (abs‘𝑁) ∈ ℤ)
40		dvdsabsb 16324	. . . . . . . 8 ⊢ (((abs‘𝑁) ∈ ℤ ∧ 𝑀 ∈ ℤ) → ((abs‘𝑁) ∥ 𝑀 ↔ (abs‘𝑁) ∥ (abs‘𝑀)))
41	39, 40	sylan 579	. . . . . . 7 ⊢ ((𝑁 ∈ ℤ ∧ 𝑀 ∈ ℤ) → ((abs‘𝑁) ∥ 𝑀 ↔ (abs‘𝑁) ∥ (abs‘𝑀)))
42	38, 41	bitrd 279	. . . . . 6 ⊢ ((𝑁 ∈ ℤ ∧ 𝑀 ∈ ℤ) → (𝑁 ∥ 𝑀 ↔ (abs‘𝑁) ∥ (abs‘𝑀)))
43	42	ancoms 458	. . . . 5 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑁 ∥ 𝑀 ↔ (abs‘𝑁) ∥ (abs‘𝑀)))
44	43	adantr 480	. . . 4 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → (𝑁 ∥ 𝑀 ↔ (abs‘𝑁) ∥ (abs‘𝑀)))
45	37, 44	mpbid 232	. . 3 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → (abs‘𝑁) ∥ (abs‘𝑀))
46		nn0abscl 15361	. . . . . . 7 ⊢ (𝑀 ∈ ℤ → (abs‘𝑀) ∈ ℕ₀)
47		nn0abscl 15361	. . . . . . 7 ⊢ (𝑁 ∈ ℤ → (abs‘𝑁) ∈ ℕ₀)
48	46, 47	anim12i 612	. . . . . 6 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((abs‘𝑀) ∈ ℕ₀ ∧ (abs‘𝑁) ∈ ℕ₀))
49		dvdseq 16362	. . . . . 6 ⊢ ((((abs‘𝑀) ∈ ℕ₀ ∧ (abs‘𝑁) ∈ ℕ₀) ∧ ((abs‘𝑀) ∥ (abs‘𝑁) ∧ (abs‘𝑁) ∥ (abs‘𝑀))) → (abs‘𝑀) = (abs‘𝑁))
50	48, 49	sylan 579	. . . . 5 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ ((abs‘𝑀) ∥ (abs‘𝑁) ∧ (abs‘𝑁) ∥ (abs‘𝑀))) → (abs‘𝑀) = (abs‘𝑁))
51	50	ex 412	. . . 4 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (((abs‘𝑀) ∥ (abs‘𝑁) ∧ (abs‘𝑁) ∥ (abs‘𝑀)) → (abs‘𝑀) = (abs‘𝑁)))
52	51	adantr 480	. . 3 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → (((abs‘𝑀) ∥ (abs‘𝑁) ∧ (abs‘𝑁) ∥ (abs‘𝑀)) → (abs‘𝑀) = (abs‘𝑁)))
53	24, 45, 52	mp2and 698	. 2 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)) → (abs‘𝑀) = (abs‘𝑁))
54		lcmid 16656	. . . . . . . 8 ⊢ ((abs‘𝑀) ∈ ℤ → ((abs‘𝑀) lcm (abs‘𝑀)) = (abs‘(abs‘𝑀)))
55	19, 54	syl 17	. . . . . . 7 ⊢ (𝑀 ∈ ℤ → ((abs‘𝑀) lcm (abs‘𝑀)) = (abs‘(abs‘𝑀)))
56		gcdid 16573	. . . . . . . 8 ⊢ ((abs‘𝑀) ∈ ℤ → ((abs‘𝑀) gcd (abs‘𝑀)) = (abs‘(abs‘𝑀)))
57	19, 56	syl 17	. . . . . . 7 ⊢ (𝑀 ∈ ℤ → ((abs‘𝑀) gcd (abs‘𝑀)) = (abs‘(abs‘𝑀)))
58	55, 57	eqtr4d 2783	. . . . . 6 ⊢ (𝑀 ∈ ℤ → ((abs‘𝑀) lcm (abs‘𝑀)) = ((abs‘𝑀) gcd (abs‘𝑀)))
59		oveq2 7456	. . . . . . 7 ⊢ ((abs‘𝑀) = (abs‘𝑁) → ((abs‘𝑀) lcm (abs‘𝑀)) = ((abs‘𝑀) lcm (abs‘𝑁)))
60		oveq2 7456	. . . . . . 7 ⊢ ((abs‘𝑀) = (abs‘𝑁) → ((abs‘𝑀) gcd (abs‘𝑀)) = ((abs‘𝑀) gcd (abs‘𝑁)))
61	59, 60	eqeq12d 2756	. . . . . 6 ⊢ ((abs‘𝑀) = (abs‘𝑁) → (((abs‘𝑀) lcm (abs‘𝑀)) = ((abs‘𝑀) gcd (abs‘𝑀)) ↔ ((abs‘𝑀) lcm (abs‘𝑁)) = ((abs‘𝑀) gcd (abs‘𝑁))))
62	58, 61	syl5ibcom 245	. . . . 5 ⊢ (𝑀 ∈ ℤ → ((abs‘𝑀) = (abs‘𝑁) → ((abs‘𝑀) lcm (abs‘𝑁)) = ((abs‘𝑀) gcd (abs‘𝑁))))
63	62	imp 406	. . . 4 ⊢ ((𝑀 ∈ ℤ ∧ (abs‘𝑀) = (abs‘𝑁)) → ((abs‘𝑀) lcm (abs‘𝑁)) = ((abs‘𝑀) gcd (abs‘𝑁)))
64	63	adantlr 714	. . 3 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (abs‘𝑀) = (abs‘𝑁)) → ((abs‘𝑀) lcm (abs‘𝑁)) = ((abs‘𝑀) gcd (abs‘𝑁)))
65		lcmabs 16652	. . . . 5 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((abs‘𝑀) lcm (abs‘𝑁)) = (𝑀 lcm 𝑁))
66		gcdabs 16577	. . . . 5 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((abs‘𝑀) gcd (abs‘𝑁)) = (𝑀 gcd 𝑁))
67	65, 66	eqeq12d 2756	. . . 4 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (((abs‘𝑀) lcm (abs‘𝑁)) = ((abs‘𝑀) gcd (abs‘𝑁)) ↔ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)))
68	67	adantr 480	. . 3 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (abs‘𝑀) = (abs‘𝑁)) → (((abs‘𝑀) lcm (abs‘𝑁)) = ((abs‘𝑀) gcd (abs‘𝑁)) ↔ (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁)))
69	64, 68	mpbid 232	. 2 ⊢ (((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (abs‘𝑀) = (abs‘𝑁)) → (𝑀 lcm 𝑁) = (𝑀 gcd 𝑁))
70	53, 69	impbida 800	1 ⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 lcm 𝑁) = (𝑀 gcd 𝑁) ↔ (abs‘𝑀) = (abs‘𝑁)))

Colors of variables: wff setvar class

Syntax hints: → wi 4 ↔ wb 206 ∧ wa 395 = wceq 1537 ∈ wcel 2108 class class class wbr 5166 ‘cfv 6573 (class class class)co 7448 ℕ₀cn0 12553 ℤcz 12639 abscabs 15283 ∥ cdvds 16302 gcd cgcd 16540 lcm clcm 16635

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1793 ax-4 1807 ax-5 1909 ax-6 1967 ax-7 2007 ax-8 2110 ax-9 2118 ax-10 2141 ax-11 2158 ax-12 2178 ax-ext 2711 ax-sep 5317 ax-nul 5324 ax-pow 5383 ax-pr 5447 ax-un 7770 ax-cnex 11240 ax-resscn 11241 ax-1cn 11242 ax-icn 11243 ax-addcl 11244 ax-addrcl 11245 ax-mulcl 11246 ax-mulrcl 11247 ax-mulcom 11248 ax-addass 11249 ax-mulass 11250 ax-distr 11251 ax-i2m1 11252 ax-1ne0 11253 ax-1rid 11254 ax-rnegex 11255 ax-rrecex 11256 ax-cnre 11257 ax-pre-lttri 11258 ax-pre-lttrn 11259 ax-pre-ltadd 11260 ax-pre-mulgt0 11261 ax-pre-sup 11262

This theorem depends on definitions: df-bi 207 df-an 396 df-or 847 df-3or 1088 df-3an 1089 df-tru 1540 df-fal 1550 df-ex 1778 df-nf 1782 df-sb 2065 df-mo 2543 df-eu 2572 df-clab 2718 df-cleq 2732 df-clel 2819 df-nfc 2895 df-ne 2947 df-nel 3053 df-ral 3068 df-rex 3077 df-rmo 3388 df-reu 3389 df-rab 3444 df-v 3490 df-sbc 3805 df-csb 3922 df-dif 3979 df-un 3981 df-in 3983 df-ss 3993 df-pss 3996 df-nul 4353 df-if 4549 df-pw 4624 df-sn 4649 df-pr 4651 df-op 4655 df-uni 4932 df-iun 5017 df-br 5167 df-opab 5229 df-mpt 5250 df-tr 5284 df-id 5593 df-eprel 5599 df-po 5607 df-so 5608 df-fr 5652 df-we 5654 df-xp 5706 df-rel 5707 df-cnv 5708 df-co 5709 df-dm 5710 df-rn 5711 df-res 5712 df-ima 5713 df-pred 6332 df-ord 6398 df-on 6399 df-lim 6400 df-suc 6401 df-iota 6525 df-fun 6575 df-fn 6576 df-f 6577 df-f1 6578 df-fo 6579 df-f1o 6580 df-fv 6581 df-riota 7404 df-ov 7451 df-oprab 7452 df-mpo 7453 df-om 7904 df-2nd 8031 df-frecs 8322 df-wrecs 8353 df-recs 8427 df-rdg 8466 df-er 8763 df-en 9004 df-dom 9005 df-sdom 9006 df-sup 9511 df-inf 9512 df-pnf 11326 df-mnf 11327 df-xr 11328 df-ltxr 11329 df-le 11330 df-sub 11522 df-neg 11523 df-div 11948 df-nn 12294 df-2 12356 df-3 12357 df-n0 12554 df-z 12640 df-uz 12904 df-rp 13058 df-fl 13843 df-mod 13921 df-seq 14053 df-exp 14113 df-cj 15148 df-re 15149 df-im 15150 df-sqrt 15284 df-abs 15285 df-dvds 16303 df-gcd 16541 df-lcm 16637

This theorem is referenced by: (None)

W3C validator