a/ ta có : 40 = 23.5 b/ ta có : 36 = 22 . 32
60 = 22.3.5 60 = 22 . 3 . 5
=> ƯCLN (40,60) = 22 . 5 = 20 72 = 23 . 32
=> ƯCLN (36,60,72) = 22 . 3 = 12
c/ Ta có : 13 = 13 d/ ta có : 28 = 22 . 7
30 = 2. 3 . 5 39 = 3 . 13
=> ƯCLN (13,30) = 1 35 = 5 . 7
=> ƯCLN (28,39,35) = 1
\(60=2^2.3.5\)
=> UCLN[40;60] = \(2^2.5=20\)
a) 40 = 23 . 5
60 = 22 . 3 . 5
ƯCLN( 40 , 60 ) = 22 . 5 = 20
b) 36 = 22 . 32
60 = 22 . 3 . 5
72 = 23 . 32
ƯCLN( 36 , 60 , 72 ) = 22 . 3 = 12
c) 13 = 13
30 = 2 . 3 . 5
ƯCLN( 13 , 30 ) = 1
d) 28 = 22 . 7
39 = 3 . 13
35 = 5 . 7
ƯCLN( 28 , 39 , 35 ) = 1