Question

phân tích các đa thức sau thành nhân tử:

a) \(^{x^3-2x^2+2x-13}\)

d) \(^{x^2-\left(a+b\right)x+ab}\)

Answer 1

\(a,=x^3-2x^2+2x-1-12=\left(x-1\right)^3-12\\ b,=x^2+ax+bx+ab\\ =x\left(x+a\right)+b\left(x+a\right)\\ =\left(x+b\right)\left(x+a\right)\)

Answer 2

a)x³-2x²+2x-13

=x³-2x²+2x-4-9

=(x³-2x²)+(2x-4)-9

=x²(x-2)+2.(x-2)-9

=(x²+2).(x-2)-9

d)x²-(a+b).x+ab

=x²-(ax+bx)+ab

=x²-ax-bx+ab

=(x²-ax)-(bx-ab)

=x.(x-a)-b.(x-a)

=(x-b).(x-a)