Determine all values of x for which f is not defined.

f(x) = (2x^3 + 5x^2 -22x + 15) / (2x^3 + 15x^2 - 34x + 24)

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- Aug 31st 2007, 04:04 AMMr_Greenfinding undefined values
Determine all values of x for which f is not defined.

f(x) = (2x^3 + 5x^2 -22x + 15) / (2x^3 + 15x^2 - 34x + 24) - Aug 31st 2007, 04:38 AMJhevon
- Aug 31st 2007, 02:27 PMtopsquark
Is there a typo here? I'm not getting a nice answer here...

You need to find where the denominator is zero, so the problem becomes how do you find the zeros of

Well, all rational zeros of this polynomial have the form

So your list of possible rational zeros is

Since none of these work you need to resort to something like Cardano's method (very ugly) or numerical approximation. I get that there is one real zero around -9.44.

-Dan