What are the possible rational zeros of f(x) = 3x4 + x3 – 13x2 – 2x + 9?

I'm so confused I thought it was this. But it's wrong?

± 1, ±1/3 , ±1/9 , ± 3

Question

What are the possible rational zeros of f(x) = 3x4 + x3 – 13x2 – 2x + 9? 

I'm so confused I thought it was this. But it's wrong?

± 1, ±1/3 , ±1/9 , ± 3

anonymous · Answer

is it multiple choice? and do you know which method they're expecting you to use?

loser66 · Answer

I don't know about the answer, I didn't solve it yet. However, the exponent of x is 4 tells me that you have at most 4 roots. Yours are 8 roots. So, it's wrong.