/ x + 2017 / + / x + 2018 / = 1
$
x < - 2018 \Rightarrow \left\{\begin{matrix}
x + 2017 < 0\\
x + 2018 < 0
\end{matrix}\right. \Rightarrow \left\{\begin{matrix}
|x + 2017| = -x - 2017\\
|x + 2018| = -x - 2018
\end{matrix}\right. \\ |x + 2017| + |x + 2018| = 1 \\ -x - 2017 - x - 2018 = 1 \\ -2x = 4036 \\ x = -2018 (loại)\\-2018 \le x < -2017 \Rightarrow \left\{\begin{matrix}
x + 2017 < 0\\
x + 2018 \ge 0
\end{matrix}\right. \Rightarrow \left\{\begin{matrix}
|x + 2017| = -x - 2017\\
|x + 2018| = x + 2018
\end{matrix}\right. \\ |x + 2017| + |x + 2018| = 1 \\ -x - 2017 + x + 2018 = 1 \\ 0 = 0 (luôn \ đúng) \\ x \ge - 2017 \Rightarrow \left\{\begin{matrix}
x + 2017 \ge 0\\
x + 2018 \ge 0
\end{matrix}\right. \Rightarrow \left\{\begin{matrix}
|x + 2017| = x + 2017\\
|x + 2018| = x + 2018
\end{matrix}\right. \\ |x + 2017| + |x + 2018| = 1 \\ x + 2017 + x + 2018 = 1 \\ 2x = -4034 \\ x = -2017 $
Vậy $ -2018 \le x \le -2017 $
[TẶNG BẠN] TRỌN BỘ Bí kíp học tốt 08 môn
