Question

\(\dfrac{27x^3}{y^{3^{ }}}\)+\(\dfrac{8y^3}{125}\)

Tl giúp em ạ

Answer 1

\(\dfrac{27x^3}{y^3}+\dfrac{8y^3}{125}\left(y\ne0\right)\\ =\left(\dfrac{3x}{y}\right)^3+\left(\dfrac{2y}{5}\right)^3\\ =\left(\dfrac{3x}{y}+\dfrac{2y}{5}\right)\left(\dfrac{9x^2}{y^2}-\dfrac{6x}{5}+\dfrac{4y^2}{25}\right)\)

Answer 2

Ta có: \(\dfrac{27x^3}{y^3}+\dfrac{8y^3}{125}\)

\(=\left(\dfrac{3x}{y}\right)^3+\left(\dfrac{2y}{5}\right)^3\)

\(=\left(\dfrac{3x}{y}+\dfrac{2y}{5}\right)\cdot\left(\dfrac{9x^2}{y^2}-\dfrac{6xy}{5y}+\dfrac{4y^2}{25}\right)\)

\(=\left(\dfrac{3x}{y}+\dfrac{2y}{5}\right)\left(\dfrac{9x^2}{y^2}-\dfrac{6x}{5}+\dfrac{4y^2}{25}\right)\)