Question

Tìm BC(12;15)

Tìm ƯC(36;54;180)

Answer 1

BCNN(12;15) = 60

ƯCLN(36;54;180) = 18 

Answer 2

BC là (60,120.....)

Answer 3

Ta có:

12=2^2.3

15=3.5

BCNN(12,15)=2^2.3.5=60

BC(12,15)=B(60)={1,2,3,4,5,6,10,12,15,20,30,60)

Answer 4

ƯC là (180)

Answer 5

1. Ta có :

B₍₁₂₎ = {0; 12; 24; 36; 48; ...}

B₍₁₅₎ = {0; 15; 30; 45; ...}

BC_(12,15) = {0; ...}

2. Ta có :

Ư₍₃₆₎ = {1; 2; 3; 4; 6; 9; 18; 12 }

Ư₍₅₄₎ = {1;2 ; 3; 6; 9; 27; 18}

Ư₍₁₈₀₎ = { 1; 2 ; 3; 4; 5; 6; 9; 10; 90; 20; 30; 60}

ƯC_(36;54;180) = {1; 2; 3; 6; 9}

Answer 6

Ta có :

12 = 3 . 2²

15 = 3 . 5

=> BC(12;15) = 3 . 2² . 5 = 60

Ta lại có 

36 = 2² . 3²

54 = 2 . 3³

180 = 2² . 5 . 3²

=>ƯC(36;54;180) = 2 . 3² = 18