Question

n +4 chia hết cho n + 2

Hướng dẫn mình nha !

Answer 1

Giải:

Ta có:

\(n+4⋮n+2\)

\(\Rightarrow\left(n+2\right)+2⋮n+2\)

\(\Rightarrow2⋮n+2\)

\(\Rightarrow n+2\in\left\{1;-1;2;-2\right\}\)

+) \(n+2=1\Rightarrow n=-1\)

+) \(n+2=-1\Rightarrow n=-3\)

+) \(n+2=2\Rightarrow n=0\)

+) \(n+2=-2\Rightarrow n=-4\)

Vậy \(n\in\left\{-1;-3;0;-4\right\}\)

Answer 2

\(n+4⋮n+2\)

\(\Rightarrow\left(n+2\right)+2⋮n+2\)

Do \(n+2⋮n+2\) nên để \(n+4⋮n+2\) thì \(2⋮n+2\)

\(\Rightarrow n+2\inƯ\left(2\right)\)

\(\Rightarrow n+2\in\left\{1;2\right\}\)

\(\Rightarrow n\in\left\{-1;0\right\}\)

Answer 3

n+4\(⋮\)n+2

(n+2)+2\(⋮\)n+2

Vì n+2\(⋮\)n+2

Buộc 2\(⋮\)n+2 mà n+2\(\ge\)2=>n+2ϵƯ(2)={2}

Với n+2=2=>n=0

Vậy n=0