\(x\left(x-\dfrac{1}{4}\right)>0\Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x>0\\x-\dfrac{1}{4}>0\end{matrix}\right.\\\left\{{}\begin{matrix}x< 0\\x-\dfrac{1}{4}< 0\end{matrix}\right.\end{matrix}\right.\left[{}\begin{matrix}\left\{{}\begin{matrix}x>0\\x>\dfrac{1}{4}\end{matrix}\right.\\\left\{{}\begin{matrix}x< 0\\x< \dfrac{1}{4}\end{matrix}\right.\end{matrix}\right.\Leftrightarrow}\left[{}\begin{matrix}x>\dfrac{1}{4}\\x< 0\end{matrix}\right.\)