Question

1)  x3 - 2x2 + x                              2) x2 – 2x – 15                             3) 3x3y2 – 6x2y3 + 9x2y2 4) 5x2y3 – 25x3y4 + 10x3y3 5) 12x2y – 18xy2 – 30y2

Answer 1

1, x^3-2x^2+x

=x^3-x^2-x^2+x

=(x^3-x^2)-(x^2-x)

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

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

=x(x-1)(x-1)

2, x^2-2x-15

=x^2-2x-9-6

= x^2-9-2x-6

=(x^2-9)-(2x+6)

=(x-3)(x+3)-2(x+3)

=(x+3)(x-3-2)=(x+3)(x-5)

3 , \(^{3x^3y^2-6x^2y^3+9x^2y^2}\)

= \(^{3x^2y^2\left(x-2y+3\right)}\)

4,  \(^{5x^2y^3-25x^3y^4+10x^3y^3}\)

=\(^{5x^2y^2\left(y-5xy^2+2xy\right)}\)

5, \(^{12x^2y-18xy^2-30y^2}\)

=\(^{3y\left(4x^2-6xy-10y\right)}\)

Answer 2

Lời giải:
1. $x^3-2x^2+x=x(x^2-2x+1)=x(x-1)^2$
2. $x^2-2x-15=(x^2+3x)-(5x+15)=x(x+3)-5(x+3)=(x+3)(x-5)$

3. $3x^3y^2-6x^2y^3+9x^2y^2=3x^2y^2(x-2y+3)$

4. $5x^2y^3-25x^3y^4+10x^3y^3=5x^2y^3(1-5xy+2x)$
5. $12x^2y-18xy^2-30y^2=6y(2x^2-3xy-5y)$