Question

7 chia hết x+2

 

Answer 1

\(\Leftrightarrow x+2\in\left\{1;-1;7;-7\right\}\)

hay \(x\in\left\{-1;-3;5;-9\right\}\)

Answer 2

\(7⋮\left(x+2\right)\\ \Rightarrow x+2\inƯ\left(7\right)=\left\{-7;-1;1;7\right\}\\ \Rightarrow x\in\left\{-9;-3;-1;5\right\}\)

Answer 3

\(x\) ∈ { -1; 5; -3; -9}