3:

a: \(40=2^3\cdot5;24=2^3\cdot3\)

=>\(ƯCLN\left(40;24\right)=2^3=8\)

=>\(ƯC\left(40;24\right)=Ư\left(8\right)=\left\{1;-1;2;-2;4;-4;8;-8\right\}\)

b: \(12=2^2\cdot3;52=2^2\cdot13\)

=>\(ƯCLN\left(12;52\right)=2^2=4\)

=>\(ƯC\left(12;52\right)=\left\{1;-1;2;-2;4;-4\right\}\)

c: \(36=2^2\cdot3^2;990=2\cdot3^2\cdot5\cdot11\)

=>\(ƯCLN\left(36;990\right)=3^2\cdot2=18\)

=>\(ƯC\left(36;990\right)=\left\{1;-1;2;-2;3;-3;6;-6;9;-9;18;-18\right\}\)

2:

a: \(12=2^2\cdot3;18=3^2\cdot2\)

=>\(ƯCLN\left(12;18\right)=2\cdot3=6\)

b: \(12=2^2\cdot3;10=2\cdot5\)

=>\(ƯCLN\left(12;10\right)=2\)

c: \(24=2^3\cdot3;48=2^4\cdot3\)

=>\(ƯCLN\left(24;48\right)=2^3\cdot3=24\)

d: \(300=2^2\cdot3\cdot5^2;280=2^3\cdot5\cdot7\)

=>\(ƯCLN\left(300;280\right)=2^2\cdot5=20\)

a) Có 12=2².3

80=2⁴.5

56=2³.7

=>ƯCLN(12,80,56)=2²=4

Vậy.....

Các câu khác bn lm tương tự nha

UCLN của :

a, 12, 80 và 56 là 4

b, 144, 120 và 135 là 9

c, 150 và 30 là 30

d, 1800 và 90 là 90

a) ƯCLN(12,80,56)=2

b) ƯCLN(144,120,135)=3

c) ƯCLN(150,30)=30

d) ƯCLN(1800,90)=18 

a: ƯCLN(40;24)=8

ƯC(40;24)=Ư(8)={1;2;4;8}

b: UCLN(80;144)=16

UCLN(80;144)={1;2;4;8;16}

c: UCLN(9;18;72)=9

ƯC(9;18;72)={1;3;9}

d: ƯCLN(25;55;75)=5

ƯC(25;55;75)={1;5}

\(a,40=2^3.5\\ 24=2^3.3\\ \Rightarrow UCLN_{\left(24;40\right)}=2^3=8\\ \RightarrowƯC_{\left(40;24\right)}=Ư_{\left(8\right)}=\left\{1;2;4;8\right\}\\ b,80=2^4.5\\ 144=2^4.3^2\\ \Rightarrow UCLN_{\left(80;144\right)}=2^4=16\\ \RightarrowƯC_{\left(80;144\right)}=Ư_{\left(16\right)}=\left\{1;2;4;8;16\right\}\\ c,9=3^2\\ 18=2.3^2\\ 72=3^2.2^3\\ \Rightarrow UCLN_{\left(8;18;72\right)}=3^2=9\\ \RightarrowƯC_{\left(9;18;72\right)}=Ư_{\left(9\right)}=\left\{1;3;9\right\}\\ d,25=5^2\\ 55=5.11\\ 75=5^2.3\\ \Rightarrow UCLN_{\left(25;55;75\right)}=5\\ \RightarrowƯC_{\left(25;55;75\right)}=Ư_{\left(5\right)}=\left\{1;5\right\}\)

Bài 1: 

a: UCLN(12;52)=4

UC(12;52)={1;2;4}

cho 1 vé báo cáo

\(a,ƯC\left(40,24\right)=Ư\left(8\right)=\left\{...\right\}\\ b,ƯC\left(12,52\right)=Ư\left(4\right)=\left\{...\right\}\\ c,ƯC\left(36,990\right)=Ư\left(18\right)=\left\{...\right\}\\ d,ƯC\left(54,36\right)=Ư\left(9\right)=\left\{...\right\}\\ e,ƯC\left(10,20,70\right)=Ư\left(10\right)=\left\{...\right\}\\ f,ƯC\left(25,55,75\right)=Ư\left(5\right)=\left\{...\right\}\\ g,ƯC\left(80,144\right)=Ư\left(16\right)=\left\{...\right\}\\ h,ƯC\left(63,2970\right)=Ư\left(9\right)=\left\{...\right\}\\ i,ƯC\left(65,125\right)=Ư\left(5\right)=\left\{...\right\}\\ j,ƯC\left(9,18,72\right)=Ư\left(9\right)=\left\{...\right\}\\ k,ƯC\left(24,36,60\right)=Ư\left(12\right)=\left\{...\right\}\\ l,ƯC\left(16,42,86\right)=Ư\left(2\right)=\left\{..\right\}\)

a:UC(40;24)=Ư(8)

b: UC(12;52)=Ư(4)

a) Ta có:

144=2⁴.3

420=2².3.5.7

ƯCLN(...)=2².3=12

ƯC(...)=Ư(12)={1;2;3;4;6;12}

Các bài sau bn cũng lm thế này nhé:)))