`<=> x - 1/4 = 0`
`<=> x = 1/4`.
Vậy `x = 1/4`.
\(\left|x-\dfrac{1}{4}\right|=0\)
TH1: \(\left|x-\dfrac{1}{4}\right|=x-\dfrac{1}{4}\) với \(x-\dfrac{1}{4}\ge0\Leftrightarrow x\ge\dfrac{1}{4}\)
Pt trở thành:
\(x-\dfrac{1}{4}=0\) (ĐK: \(x\ge\dfrac{1}{4}\))
\(\Leftrightarrow x=\dfrac{1}{4}\left(tm\right)\)
TH2: \(\left|x-\dfrac{1}{4}\right|=-\left(x-\dfrac{1}{4}\right)\) với \(x-\dfrac{1}{4}< 0\Leftrightarrow x< \dfrac{1}{4}\)
Pt trở thành:
\(-\left(x-\dfrac{1}{4}\right)=0\) (ĐK: \(x< \dfrac{1}{4}\))
\(\Leftrightarrow-x+\dfrac{1}{4}=0\)
\(\Leftrightarrow-x=-\dfrac{1}{4}\)
\(\Leftrightarrow x=\dfrac{1}{4}\left(ktm\right)\)
Vậy \(S=\left\{\dfrac{1}{4}\right\}\)
