Trl :
( Sai thì thôi nha )
\(56=2^3.7\)
\(140=2^2.5.7\)
Vậy ƯCLN( 56;140 ) = \(2^2.7=28\)
Câu tiếp theo :
\(24=2^3.3\)
\(84=2^2.3.7\)
\(180=2^2.3^2.5\)
Vậy ƯCLN( 24;84;180 ) = \(2^2.3=12\)
Ta có:56=23.7
140=22.5.7
\(\Rightarrow\)ƯCLN(56,140)=22.7=28
Vậy ƯCLN(56,140)=28
Ta xó:24=23.3
84=22.3.7
180=22.32.5
\(\Rightarrow\)ƯCLN(24,84,180)=22.3=12
Vậy ƯCLN(24,84,180)=12