\(n+7⋮\left(n+5\right)\)
\(\Rightarrow n+5+2⋮\left(n+5\right)\)
\(\Rightarrow2⋮\left(n+5\right)\Rightarrow\left(n+5\right)\inƯ\left(2\right)=\left\{\pm1;\pm2\right\}\)
\(\Rightarrow n\in\left\{-4;-6;-7;-3;\right\}\)
n + 7 là bội của n + 5
\(\Rightarrow n+7⋮n+5\)
\(\Rightarrow n+5+2⋮n+5\)
Mà : \(n+5⋮n+5\)suy ra : \(2⋮n+5\)
\(\Rightarrow n+5\inƯ\left(2\right)=\left\{-2;-1;1;2\right\}\)
\(\Rightarrow n\in\left\{-7;-6;-4;-3\right\}\)