Question

tìm BCNN của : 

a/ 10, 12,15

b/ 8 ,9,11

c/ 24,40,168

Answer 1

a)
Ta có:
10 = 2.5
12 = 2².3
15 = 3.5
BCNN(10;12;15) = 2².5.3 = 60
b)
8 = 2³
9 = 3²
11 = 11
BCNN(8;9;22) = 2³.3².11 = 792
c)
24 = 2³.3
40 = 2³.5
168 = 2³.3.7

BCNN(24;40;168) = 2³.3.5.7 = 840

Answer 2

a, 10=2.5

    12=2².3

    15=3.5

=>BCNN(10;12;15)=2².3.5=60

b, 8=2³

    9=3²

    11=11.1

=> BCNN(8;9;11)=2³.3².11=792