\(\Leftrightarrow2n+2-5⋮n+1\)
\(\Leftrightarrow n+1\in\left\{1;-1;5;-5\right\}\)
hay \(n\in\left\{0;-2;4;-6\right\}\)
\(\dfrac{2n-3}{n+1}=\dfrac{n+1+n+1-5}{n+1}=1+1-\dfrac{5}{n+1}\)
Để \(2n-3⋮n+1\) thì \(5⋮n+1\) hay \(n+1\in U\left(5\right)=\left\{\pm1;\pm5\right\}\)
n+1=1 => n=0
n+1=-1 => n=-2
n+1=5 => n=4
n+1=-5 => n=-6
Vậy \(n\in\left\{0;-2;4;-6\right\}\)
học ngu sẵn r trônng chờ làm gì