Here's the question you clicked on:
DeadShot
What are the possible number of positive, negative, and complex zeros of f(x) = 3x^4 - 5x^3 - x^2 - 8x + 4 ?
Well, if they just want the number of roots, then it will be a total of 4 , 2 complex, 2 reals
My teacher wants the possible number of positive real, negative real, and complex. Knowing that there are 2 complex zeroes narrows down the answer.
Is the number of positive real 3 or 1 and the negative 1, or is it vice versa?
Then apply Descartes' Rule, have you learn that before?
I have to go now, there's a tutorial on that here: http://www.purplemath.com/modules/drofsign.htm Try it out :)