a)Ta có 60 = 2 2 .3. 5; 280 = 2 3 .5.7

BCNN(60; 280) =  2 3 . 3.5.7= 840

b) Ta có: 84 =  2 2 .3.7; 108 =  2 2 . 3 3

BCNN(84; 108) =  2 2 . 3 3 .7 = 756

c) Ta có: 13 =13; 15= 3.5

BCNN(13; 15) = 13.3.5= 195.

d) Ta có; 10 = 2.5; 12 =  2 2 .3; 15 = 3.5

BCNN(10;12; 15) =  2 2 .3.5 = 60

e) Ta có: 8 = 2 3 ; 9 =  3 2 ; 11 = 11

BCNN(8; 9; 11) = 2 3 . 3 2 .11= 792

f) Ta có: 24 = 3. 2 3 ; 40 =  2 3 .5; 168 =  2 3 .3.7

BCNN(24; 40; 168)=  2 3 .3. 5.7= 840

a

khó quá ! em mới học lớp 5 thôi à

a: \(24=2^3\cdot3;10=2\cdot5\)

=>BCNN(24;10)=\(2^3\cdot3\cdot5=8\cdot15=120\)

=>BC(24;10)=B(120)={120;240;360;...}

b: \(60=2^2\cdot3\cdot5;128=2^7\)

=>BCNN(60;128)=\(2^7\cdot3\cdot5=128\cdot15=1920\)

=>BC(60;128)=B(1920)={1920;3840;...}

c: \(98=2\cdot7^2;72=2^3\cdot3^2\)

=>BCNN(98;72)=\(2^3\cdot3^2\cdot7^2=3528\)

=>BC(98;72)=B(3528)={3528;7056;...}

d: \(10=2\cdot5;12=2^2\cdot3;15=3\cdot5\)

=>BCNN(10;12;15)=\(2^2\cdot3\cdot5=60\)

=>BC(10;12;15)=B(60)={60;120;180;...}

e: \(56=2^3\cdot7;70=2\cdot5\cdot7;126=2\cdot3^2\cdot7\)

=>BCNN(56;70;126)=\(2^3\cdot3^2\cdot5\cdot7=2520\)

=>BC(56;70;126)=B(2520)={2520;5040;...}

f: \(8=2^3;12=2^2\cdot3;15=3\cdot5\)

=>BCNN(8;12;15)=\(2^3\cdot3\cdot5=8\cdot3\cdot5=120\)

=>BC(8;12;15)=B(120)={120;240;360;...}

a. Ta có: 
24 = 2³ . 3
10 = 2 . 5
BCNN (24,10) = 2³. 3 . 5 = 120
BC (24,10) = B (120) = {0; 120; 240; 360; 480; 600; ....}

Bạn dựa vào câu a) làm những câu còn lại nhé!

a: \(24=2^3\cdot3;10=2\cdot5\)

=>BCNN(24;10)=\(2^3\cdot3\cdot5=8\cdot15=120\)

=>BC(24;10)=B(120)={120;240;360;...}

b: \(60=2^2\cdot3\cdot5;128=2^7\)

=>BCNN(60;128)=\(2^7\cdot3\cdot5=128\cdot15=1920\)

=>BC(60;128)=B(1920)={1920;3840;...}

c: \(98=2\cdot7^2;72=2^3\cdot3^2\)

=>BCNN(98;72)=\(2^3\cdot3^2\cdot7^2=3528\)

=>BC(98;72)=B(3528)={3528;7056;...}

d: \(10=2\cdot5;12=2^2\cdot3;15=3\cdot5\)

=>BCNN(10;12;15)=\(2^2\cdot3\cdot5=60\)

=>BC(10;12;15)=B(60)={60;120;180;...}

e: \(56=2^3\cdot7;70=2\cdot5\cdot7;126=2\cdot3^2\cdot7\)

=>BCNN(56;70;126)=\(2^3\cdot3^2\cdot5\cdot7=2520\)

=>BC(56;70;126)=B(2520)={2520;5040;...}

f: \(8=2^3;12=2^2\cdot3;15=3\cdot5\)

=>BCNN(8;12;15)=\(2^3\cdot3\cdot5=8\cdot3\cdot5=120\)

=>BC(8;12;15)=B(120)={120;240;360;...}

a: BCNN(60;280)=840

b: BCNN(84;108)=756

c: BCNN(5;8;15)=120

d: BCNN(12;16;48)=48

bạn nên chia nhỏ đề bài ra

cái này dễ mak bn ơi,bn đăng

từng bài một mn sẽ giải chứ

bn đăng như này chưa chắc

đã cs ng giải cho bn

\(a,24=2^3\cdot3; 10=2\cdot5\\ ƯCLN\left(10,24\right)=2\\ BCNN\left(10,24\right)=2^3\cdot3\cdot5=120\\ b,9=3^2; 24=2^3\cdot3\\ ƯCLN\left(9,24\right)=3\\ BCNN\left(9,24\right)=2^3\cdot3^2=72\\ c,12=2^2\cdot3; 52=2^2\cdot13\\ ƯCLN\left(12,52\right)=2^2=4\\ BCNN\left(12,52\right)=2^2\cdot3\cdot13=156\\ d,14=2\cdot7;21=3\cdot7;56=2^3\cdot7\\ ƯCLN\left(14,21,56\right)=7\\ BCNN\left(14,21,56\right)=2^3\cdot3\cdot7=168\\ e,8=2^3;12=2^2\cdot3;15=3\cdot5\\ ƯCLN\left(8,12,15\right)=1\\ BCNN\left(8,12,15\right)=2^3\cdot3\cdot5=120\\ f,6=2\cdot3;8=2^3;10=2\cdot5\\ ƯCLN\left(6,8,10\right)=2\\ BCNN\left(6,8,10\right)=2^3\cdot3\cdot5=120\)

a,

56=2³.7

140=2².5.7

=>ƯCLN(56,140)=2².7=28

60=2².3.5

180=2².3².5

=>ƯCLN(60,180)=2².3.5=60

b,

84=2².3.7

108=2².3³

=>BCNN(84,108)=2².3³.7=756

24=2³.3

40=2³.5

168=2³.3.7

=>BCNN(24,40,168)=2³.3.5.7=840

Tick giúp mình với nhá!