a: |x|=5
=>x=5 hoặc x=-5
b: |x|=1/2
=>x=1/2 hoặc x=-1/2
c: |x-1|=0,25
=>x-1=0,25 hoặc x-1=-0,25
=>x=0,75 hoặc x=1,25
d: =>|2x+1/2|=29/8
=>2x+1/2=29/8 hoặc 2x+1/2=-29/8
=>2x=25/8 hoặc 2x=-33/8
=>x=25/16 hoặc x=-33/16
a) \(\left|x\right|=5\)
\(\Rightarrow\left[{}\begin{matrix}x=5\\x=-5\end{matrix}\right.\)
b) \(\left|x\right|=\dfrac{1}{2}\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=-\dfrac{1}{2}\end{matrix}\right.\)
c) \(\left|x-1\right|=0,25\)
\(\Rightarrow\left[{}\begin{matrix}x-1=0,25\\x-1=-0,25\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=0,25+1\\x=-0,25+1\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=1,25\\x=0,75\end{matrix}\right.\)
d) \(\left|2x-\dfrac{1}{2}\right|=3\dfrac{5}{8}\)
\(\Rightarrow\left|2x-\dfrac{1}{2}\right|=\dfrac{29}{8}\)
\(\Rightarrow\left[{}\begin{matrix}2x-\dfrac{1}{2}=\dfrac{29}{8}\\2x-\dfrac{1}{2}=-\dfrac{29}{8}\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}2x=\dfrac{29}{8}+\dfrac{1}{2}\\2x=-\dfrac{29}{8}+\dfrac{1}{2}\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}2x=\dfrac{33}{8}\\2x=-\dfrac{25}{8}\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{33}{8}:2\\x=-\dfrac{25}{8}:2\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{33}{16}\\x=-\dfrac{25}{16}\end{matrix}\right.\)
