2X^4-9X^3+13X^2-X-5=0

Question

Given that one root is 2+i, solve the equation.

So far I have it set up like this:

2X^4-9X^3+13X^2-X-5/X^2-4X+5

I don't know how to get the answer, I know that I have to use long division but when I started to try it I kept getting weird answers. Please Help

Answer 1

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