Question

tính: 5x^2 - 5y^2 - 10x + 10y

  x^3+ x^2y - 4x - 4y

  x^3 - x^2 - x + 1

  X^3 - y^3 +3x^2 + 3x + 1

help vs ạ mk cần gấp lắm plssssssssss 

Answer 1

\(a,=5\left(x^2-y^2\right)-10\left(x-y\right)=5\left(x-y\right)\left(x+y\right)-10\left(x-y\right)=\left(x-y\right)\left[5\left(x+y\right)-10\right]\\----------\\ b,=x^2\left(x+y\right)-4\left(x+y\right)=\left(x^2-4\right)\left(x+y\right)=\left(x-2\right)\left(x+2\right)\left(x+y\right)\\ ----------\\ c,=x^2\left(x-1\right)-\left(x-1\right)=\left(x^2-1\right)\left(x-1\right)=\left(x-1\right)^2\left(x+1\right)\\ ----------\\ d,Sửa:x^3-3x^2+3x-1-y^3=\left(x-1\right)^3-y^3=\left[\left(x-1\right)-y\right]\left[\left(x-1\right)^2+\left(x-1\right).y+y^2\right]\)