Determine the rational roots of 2x 5 - 11x 4 + 14x 3 - 2x 2 + 12x + 9 = 0.

Question

anonymous · Answer

I really need help with this question. :)

mertsj · Answer

Have you made a list of the possible rational roots?

anonymous · Answer

Not yet.

mertsj · Answer

Do that and then test them using synthetic division until you find one whose remainder is 0

anonymous · Answer

Ok. I've done that step. Is the possible answer, 1/2, 1, 3/2, 3, 9/2 and 9?

mertsj · Answer

The possible rational roots are:
$$\pm1, \pm3, \pm9, \pm\frac{1}{2}, \pm\frac{3}{2}, \pm\frac{9}{2}$$

anonymous · Answer

That's what I got. :) Thanks so much!

mertsj · Answer

That is NOT the answer.  You do know that, right?

mertsj · Answer

The problem says to find the rational roots.  Step 1 is to make a list of the possibilities.  That is what we have done so far.

anonymous · Answer

Ok. What do we do next?

mertsj · Answer

Do that and then test them using synthetic division until you find one whose remainder is 0

mertsj · Answer

Do you know how to do that?

anonymous · Answer

No, not really. Can you help me with that?

mertsj · Answer

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