\(c,5xy\sqrt{\dfrac{25x^2}{y^6}}=\dfrac{5xy\left|5x\right|}{\left|y^3\right|}=\dfrac{5xy\left(-5x\right)}{y^3}=\dfrac{-25x^2y}{y^3}=\dfrac{-25x^2}{y^2}\)
\(d,=\dfrac{0,2x^3y^3\cdot4}{\left|x^2y^4\right|}=\dfrac{0,8x^3y^3}{x^2y^4}=\dfrac{0,8x}{y}=\dfrac{\dfrac{4}{5}x}{y}=\dfrac{5x}{4y}\)