Question

phân tích đa thức thành nhân tử. 
 ab (x^2 +y^2 ) -xy(a^2 +b^2)

Answer 1

\(abx^2+aby^2-a^2xy-b^2xy\\ =\left(abx^2-a^2xy\right)+\left(aby^2-b^2xy\right)\\ =ax\left(bx-ay\right)+by\left(ay-bx\right)\\ =ax\left(bx-ay\right)-by\left(bx-ax\right)\\ =\left(ax-by\right)\left(by-ax\right)\)

Answer 2

`a, abx^2 + aby^2 - xya^2 - xyb^2`

`= ax(bx - ay) - by(bx - ay)`

 `=(ax-by)(bx-ay)`

Answer 3

\(ab\left(x^2+y^2\right)-xy\left(a^2+b^2\right)=abx^2+aby^2-a^2xy-b^2xy\)

\(ax\left(bx-ay\right)+by\left(ay-bx\right)=\left(-ay+bx\right)\left(ax-by\right).\)