Kết quả phép tính \(\dfrac{3x^2-6xy+3y^2}{5x^2-5xy+5y^2}:\dfrac{10x-10y}{x^3+y^3}\) là
\(\dfrac{3x^2-y^2}{50}.\)\(\dfrac{3\left(x^2+y^2\right)}{50}.\)\(\dfrac{3\left(x^2-y^2\right)}{50}.\)\(\dfrac{3x^2+y^2}{50}.\)Hướng dẫn giải:\(\dfrac{3x^2-6xy+3y^2}{5x^2-5xy+5y^2}:\dfrac{10x-10y}{x^3+y^3}\)
\(=\dfrac{3\left(x-y\right)^2}{5\left(x^2-xy+y^2\right)}.\dfrac{\left(x+y\right)\left(x^2-xy+y^2\right)}{10\left(x-y\right)}\)
\(=\dfrac{3\left(x-y\right)\left(x+y\right)}{50}=\dfrac{3\left(x^2-y^2\right)}{50}.\)
