Question

Tìm n có giá trị nguyên :

\(\dfrac{6}{n-1}\)

Answer 1

Để \(\dfrac{6}{n-1}\) thì 6⋮n-1

n-1∈Ư(6)

Ư(6)={1;-1;2-2;3;-3;-6;6}

n∈{2;0;3;-1;4;-2;-5;7}

Answer 2

Tích giúp c nha!

Answer 3

\(\dfrac{6}{n-1}\) là số nguyên dương\(\Leftrightarrow6⋮\left(n-1\right)\)

\(\Leftrightarrow\left[{}\begin{matrix}n-1=1\\n-1=2\\n-1=3\\n-1=6\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}n=2\\n=3\\n=4\\n=7\end{matrix}\right.\)

Answer 4

Để n có giá trị nguyên

\(\Leftrightarrow n-1\inƯ\left(6\right)=\left\{-6;-3;-2;-1;1;2;3;6\right\}\)

\(\Rightarrow n=\left\{-5;-2;-1;0;2;3;4;7\right\}\)

Answer 5

Để phân số 6/n-1 có giá trị nguyên thì \(n-1\in\left\{1;-1;2;-2;3;-3;6;-6\right\}\)

hay \(n\in\left\{2;0;3;-1;4;-2;7;-5\right\}\)