How do you factor x^3 - 2x^2 - x + 2 x32x2x+2?

2 Answers
May 22, 2015

We can factor out xx from all the elements that contain it:

x(x^2-2x-x)-2x(x22xx)2

And then factor the quadratic inside the parenthesis, which, using Bhaskara, will give us the following roots:

(2+-sqrtcancel((4-4(1)(1))))/2
2/2=1

x_1=x_2=1

Thus, the factors are both (x-1)

Finally: x((x-1)(x-1))+2

May 22, 2015

Factor by grouping:

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

=(x^3-2x^2)+(-x+2) (Notice the inserted addition before the second pair.)

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

=(x^2-1)(x-2) Now the first binomial is a difference of squares, so

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

x^3-2x^2-x+2=(x+1)(x-1)(x-2)