How do you factor x3+10x2+33x+34?

1 Answer
Jul 8, 2016

x3+10x2+33x+34==(x2+8x+17)(x+2)

Explanation:

As putting x=2, we get x3+10x2+33x+34=(2)3+10×22+33×(2)+34=8+4066+34=0. Hence, 2 is a zero of the function and (x+2) is a factor of x3+10x2+33x+34.

Now dividing the function by (x+2), as x3+10x2+33x+34==x2(x+2)+8x(x+2)+17(x+2)=(x2+8x+17)(x+2), we get x2+8x+17.

Now discriminant of x2+8x+17 is 824117=6468=4 is negative, as such it cannot be factorized in real factors.

And hence factors of the function are

x3+10x2+33x+34==(x2+8x+17)(x+2)