Question

Bài 6: Phân tích đa thức thành nhân tử:
1, A=(x + y)²-x³-y³.
3, A = (x+y)' +(x-y)'.
2, A=x³ +1-x²-x.
4, A=x³-4x² +8x-8.

Answer 1

`(1):`

`A=(x+y)^{2}-x^{3}-y^{3}`

`=(x+y)^{2}-(x^{3}+y^{3})`

`=(x+y)^{2}-(x+y)(x^{2}-xy+y^{2})`

`=(x+y)(x+y-x^{2}+xy-y^{2})`

``

`(2):`

`A=x^{3}+1-x^{2}-x`

`=(x^{3}-x^{2})-(x-1)`

`=x^{2}(x-1)-(x-1)`

`=(x-1)(x^{2}-1)`

`=(x-1)^{2}(x+1)`

`(4):`

`A=x^{3}-4x^{2}+8x-8`

`=(x^{3}-2^{3})-(4x^{2}-8x)`

`=(x-2)(x^{2}+2x+4)-4x(x-2)`

`=(x-2)(x^{2}+2x+4-4x)`

`=(x-2)(x^{2}-2x+4)`

Answer 2

2: =(x+1)(x^2-x+1)-x(x+1)

=(x+1)(x^2-2x+1)

=(x+1)(x-1)^2

4: \(=\left(x-2\right)\left(x^2+2x+4\right)-4x\left(x-2\right)\)

\(=\left(x-2\right)\left(x^2-2x+4\right)\)