x\(\sqrt{\dfrac{x}{y^3}}\)=x\(\sqrt{\dfrac{xy}{y^4}}\)=x\(\sqrt{\dfrac{xy}{\left(y^2\right)^2}}\)=\(\dfrac{x}{y^2}\sqrt{xy}\)(y2>0)
vậy (A) là đáp án đúng.
\(x\sqrt{\dfrac{x}{y^3}}=x\sqrt{\dfrac{xy}{y^4}}=x\sqrt{\dfrac{x}{\left(y2\right)^2}}=\dfrac{x}{y^2}\sqrt{xy}\left(y^2>0\right)\)
\(Vậy\) \(đáp\) \(án\) \(đúng\) \(là\) \(A.\)