\(\left|x-3\right|=\left|2x+15\right|\)
\(\Rightarrow\orbr{\begin{cases}2x+15=x-3\\2x+15=3-x\end{cases}\Leftrightarrow\orbr{\begin{cases}x=-18\\x=-4\end{cases}}}\)
KL:..................................................................
\(\left|2x-4\right|+\left|2x-6\right|=2\)
\(\Rightarrow\left|2x-4\right|+\left|6-2x\right|=2\)
Ta có: \(\hept{\begin{cases}\left|2x-4\right|\ge2x-4\forall x\\\left|6-2x\right|\ge6-2x\forall x\end{cases}\Rightarrow\left|2x-4\right|+\left|6-2x\right|\ge2x-4+6-2x=2\forall x}\)
Mà \(\left|2x-4\right|+\left|2x-6\right|=2\)
Dấu "=" xảy ra \(\Leftrightarrow\hept{\begin{cases}\left|2x-4\right|=2x-4\\\left|6-2x\right|=6-2x\end{cases}\Leftrightarrow\hept{\begin{cases}2x-4\ge0\\6-2x\ge0\end{cases}\Leftrightarrow}\hept{\begin{cases}x\ge2\\x\le3\end{cases}\Rightarrow}2\le x\le3}\)
KL:.............................................................
Câu c tương tự câu b
