Please help, this deals with the whole section.

Question

anonymous · Answer

Find all rational zeros of the polynomial. (Enter your answers as a comma-separated list. If a zero has multiplicity greater than one, only enter the root once.)
$$P(x) = 10x^4 − 13x^3 − 198x^2 + 61x + 20$$

anonymous · Answer

I really need help please. All the problems in this section are like this.

yttrium · Answer

Do you know something about factor theorem?

yttrium · Answer

I think it's a matter of trial and error. (for the first factor)

anonymous · Answer

Well, thats the hard part. There is an easier way but I do not know how to do it. The upper and lower bounds to shorten your search.

anonymous · Answer

Without narrowing it down, I would be testing about 15+ equations through synthetic division.

yttrium · Answer

Ooohhh. I somewhat remember it. You can let p as the factor of the coefficient and you can let q as the factor of the leading coefficient. And to find the possible roots, you have to apply p/q.

yttrium · Answer

In your case. It must be factors of 20 over factors of 10. That is: (20 or 10 or 5 or 4 or 2 or 1) over (10 or 5 or 2 or 1)

yttrium · Answer

So what are the possible roots, then? @genson0 ?