a/ \(\left|2,5-x\right|=1,3\)
\(\Leftrightarrow\left[{}\begin{matrix}2,5-x=1,3\\2,5-x=-1,3\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=1,2\\x=3,8\end{matrix}\right.\)
Vậy .
b/ \(1,6-\left|x-0,2\right|=0\)
\(\Leftrightarrow\left|x-0,2\right|=1,6\)
\(\Leftrightarrow\left[{}\begin{matrix}x-0,2=1,6\\x-0,2=-1,6\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=1,8\\x=-1,4\end{matrix}\right.\)
Vậy ....
c/ \(\left|x-1,5\right|+\left|2,5-x\right|=0\)
Mà \(\left\{{}\begin{matrix}\left|x-1,5\right|\ge0\\\left|2,5-x\right|\ge0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}\left|x-1,5\right|=0\\\left|2,5-x\right|=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x-1,5=0\\2,5-x=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x=1,5\\x=2,5\end{matrix}\right.\) (loại)
Vậy ..........
\(a)\left|2,5-x\right|=1,3\)
\(\Rightarrow\left[{}\begin{matrix}2,5-x=1,3\\2,5-x=-1,3\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=1,2\\x=3,8\end{matrix}\right.\)
Vậy .....
\(b)1,6-\left|x-0,2\right|=0\)
\(\Rightarrow\left|x-0,2\right|=1,6-0\)
\(\Rightarrow\left|x-0,2\right|=0\)
\(\Rightarrow x-0,2=0\)
\(\Rightarrow x=0,2\)
Vậy .......
\(c)\left|x-1,5\right|+\left|2,5-x\right|=0\)
\(\Rightarrow\left[{}\begin{matrix}x-1,5=0\\2,5-x=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=1,5\\x=2,5\end{matrix}\right.\)
Vậy .....
Chúc bạn học tốt!
a) \(\left|2.5-x\right|=1.3\\ \Leftrightarrow\left\{{}\begin{matrix}2.5-x=1.3\\2.5-x=-1.3\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=1.2\\x=3.8\end{matrix}\right.\)
b) \(1.6-\left|x-0.2\right|=0 \Leftrightarrow\left|x-0.2\right|=1.6\\ \Leftrightarrow\left\{{}\begin{matrix}x-0.2=1.6\\x-0.2=-1.6\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=1.8\\x=-1.4\end{matrix}\right.\)
c)\(\left|x-1.5\right|+\left|2.5-x\right|=0\)
Vì \(\left|x-1.5\right|\ge0\) và \(\left|2.5-x\right|\ge0\)
\(\Rightarrow\left|x-1.5\right|+\left|2.5-x\right|>0\) với mọi x
Vậy x ko có.
