Câu hỏi của Long Hung

Question

tim tat ca cac so nguyen a biet 3a+1chia het cho a-1

Nguyễn Việt Lâm · Accepted Answer

$3a+1⋮a-1\Leftrightarrow3\left(a-1\right)+4⋮a-1$

$\Leftrightarrow4⋮a-1\Rightarrow a-1=Ư\left(4\right)=\left\{-4;-2;-1;1;2;4\right\}$

$\Rightarrow a=\left\{-3;-1;0;2;3;5\right\}$Câu trả lời: $3a+1⋮a-1\Leftrightarrow3\left(a-1\right)+4⋮a-1$

$\Leftrightarrow4⋮a-1\Rightarrow a-1=Ư\left(4\right)=\left\{-4;-2;-1;1;2;4\right\}$

$\Rightarrow a=\left\{-3;-1;0;2;3;5\right\}$

Chương II : Số nguyên