# Thread: factoring a quartic function

1. ## factoring a quartic function

I'm not sure how to factor or solve this problem without graphing, but I know the answer comes to be positive and negative rad 5 and positive and negative rad 2. I need to know how to go through the process to find these 4 answers.

here's the formula:
0=x^4-2x^3-6x^2+4x+8

thanks so much if you can help!!

2. Replace the $6x^{2}$ with $-4x^{2}-2x^{2}$, then group.

$(x^{4}-2x^{3}-4x^{2})-(2x^{2}+4x+8)$

Factor:

$x^{2}(x^{2}-2x-4)-2(x^{2}-2x-4)$

$(x^{2}-2)(x^{2}-2x-4)$

Now, you can solve each of the quadratics for their two solutions and you're set.

All the solutions are real.