a, |x - 0,25 | = 1
\(\Rightarrow\left[{}\begin{matrix}x-0,25=1\\x-0,25=-1\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0,25\\x=-0,75\end{matrix}\right.\)
Vậy x ∈ {0,25 ; -0,75}
b, \(\left|x+\dfrac{1}{4}\right|-\dfrac{1}{2}=0\)
\(\Rightarrow\left|x+\dfrac{1}{4}\right|=\dfrac{1}{2}\)
\(\Rightarrow\left[{}\begin{matrix}x+\dfrac{1}{4}=\dfrac{1}{2}\\x+\dfrac{1}{4}=-\dfrac{1}{2}\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{1}{4}\\x=-\dfrac{3}{4}\end{matrix}\right.\)
Vậy \(x\in\left\{\dfrac{1}{4};-\dfrac{3}{4}\right\}\)
a: \(\left|x-\dfrac{1}{4}\right|=1\)
\(\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{1}{4}=1\\x-\dfrac{1}{4}=-1\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{4}\\x=\dfrac{3}{4}\end{matrix}\right.\)
