tìm ưc (36,42) tìm bc (12,160

a) Ta có :

` 36 = 2^2 . 3^2`

` 42 = 2 . 3 . 7`

` => Ư CLN(36,42) = 2 . 3 = 6`

` => Ư C(36,42) = {+-1 ; +-2 ; +-3 ; +-6}` 

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b) Ta có :

` 12 = 2^2 . 3`

` 160 = 2^5 . 5`

` => \text{BCNN(12,160)} = 2^5 . 3 . 5 = 480`

` => BC(12,160) = {0 ; +-480 ; +-960 ;...}`