Question

Làm tính chia (x³+8y³):(x+2y)

Answer 1

\(\left(x^3+8y^3\right):\left(x+2y\right)=\left(x^3+2^3y^3\right):\left(x+2y\right)=\left[x^3+\left(2y\right)^3\right]:\left(x+2y\right)\)

Áp dụng hằng đẳng thức : \(a^3+b^3=\left(a+b\right)\left(a^2-ab+b^2\right)\)

\(\left[x^3+\left(2y\right)^3\right]:\left(x+2y\right)=\left[\left(x+2y\right).\left(x^2-2xy+4y^2\right)\right]:\left(x+2y\right)=x^2-2xy+4y^2\)