\(a,ƯC\left(16,24\right)=Ư\left(8\right)=\left\{\pm1;\pm2;\pm4;\pm8\right\}\\ b,BC\left(84,108\right)=B\left(756\right)=\left\{0;756;1512;2268;...\right\}\\ c,ƯC\left(36,48,120\right)=Ư\left(12\right)=\left\{\pm1;\pm2;\pm3;\pm4;\pm6;\pm12\right\}\\ d,BC\left(42,64,70\right)=B\left(6720\right)=\left\{0;6720;13440;20160;...\right\}\)

Sai

Sai

Đúng 

Bài 2:

33 = 3.11 ; 54 = 2.3^3

=> UCLN(33;54) = 3 

=> 2 B của 33;54 là 1;3

=> BCNN(33;54) = 3^3.11.2 = 594

2 Ư của 33;54 là 0 và 594       

a : sai

b : sai

c: đúng

Bài 2

a ư33 =1 ; 3

b33=66;594

ư54=1;3

b54=108;594

b ưc(33;54)=1;3

bc(33;54)=594;1188

a) \(ƯC_{a;a+1}=\left\{1\right\}\)
b) \(BC_{2;5}=\left\{10;20;30;40;50....\right\}\)

gd

a, 72 = 2³.3²;    24 = 2³.3 

ƯCLN(72; 24) = 2³.3 = 24

ƯC(72; 24) = { 1; 2; 3; 4; 6; 8; 12; 24}

b, 30; 60; 20

 30 = 2.3.5;                 60 = 2².3.5;                 20 = 2.5

 ƯCLN(30; 60; 20) = 2.5 = 10

ƯC(30; 60; 20) = { 1; 2; 5; 10}

ƯC(45;180;120)={1;3;5;15}

BC(45;180;120)=B(360)