1 câu trả lời
$\begin{array}{l} 3:\left( {x - \dfrac{1}{2}} \right) = \left( {x - \dfrac{1}{2}} \right):27\\ \Rightarrow \dfrac{3}{{x - \frac{1}{2}}} = \dfrac{{x - \frac{1}{2}}}{{27}}\\ \Rightarrow {\left( {x - \dfrac{1}{2}} \right)^2} = 3.27\\ \Rightarrow {\left( {x - \dfrac{1}{2}} \right)^2} = 81 = {9^2} = {\left( { - 9} \right)^2}\\ \Rightarrow \left[ \begin{array}{l} x - \dfrac{1}{2} = 9\\ x - \dfrac{1}{2} = - 9 \end{array} \right. \Rightarrow \left[ \begin{array}{l} x = 9 + \dfrac{1}{2}\\ x = - 9 + \dfrac{1}{2} \end{array} \right. \Rightarrow \left[ \begin{array}{l} x = \dfrac{{19}}{2}\\ x = \dfrac{{ - 17}}{2} \end{array} \right. \end{array}$
