Đáp án:
1,
\(\left[ \begin{array}{l}
x + 3 = 1\\
x + 3 = - 1
\end{array} \right.\)
2,\(\Rightarrow x \in \left\{ { - 8, - 4, - 2, - 1,1,2,4,8} \right\}\)
3, \(x \in \left\{ { - 6, - 4, - 3, - 1,0,2} \right\}\)
Giải thích các bước giải:
\(\begin{array}{l}
1,(x + 4) \vdots (x + 3)\\
\Rightarrow (x + 3) + 1 \vdots (x + 3)\\
\Rightarrow 1 \vdots (x + 3)\\
\Rightarrow \left[ \begin{array}{l}
x + 3 = 1\\
x + 3 = - 1
\end{array} \right.\\
\Leftrightarrow \left[ \begin{array}{l}
x = - 2\\
x = - 4
\end{array} \right.\\
2,(x + 8) \vdots x\\
\Rightarrow 8 \vdots x\\
\Rightarrow x \in \left\{ { - 8, - 4, - 2, - 1,1,2,4,8} \right\}\\
3,(x + 6) \vdots (x + 2)\\
\Rightarrow (x + 2) + 4 \vdots (x + 2)\\
\Rightarrow 4 \vdots (x + 2)\\
\Rightarrow x + 2 \in \left\{ { - 4, - 2, - 1,1,2,4} \right\}\\
\Rightarrow x \in \left\{ { - 6, - 4, - 3, - 1,0,2} \right\}
\end{array}\)
