Question

Answer 1

1. 

\(a,ƯCLN\left(45,75\right)=5\\ b,ƯCLN\left(36,64,72\right)=4\\ c,ƯCLN\left(15,26\right)=1\)

2. 

\(a,ƯC\left(84,72\right)=Ư\left(12\right)=\left\{...\right\}\\ b,ƯC\left(120,180,256\right)=Ư\left(8\right)=\left\{...\right\}\)

3. 

\(x=ƯCLN\left(360,420\right)=60\)

4.

\(ƯC\left(126,210\right)=Ư\left(42\right)\\ \Leftrightarrow x=21\)

Answer 2

Câu 4:

\(126⋮x\)

\(210⋮x\)

Do đó: \(x\in\left\{1;2;3;6;7;14;21;42\right\}\)

hay x=21