Correct answer is 1, -1, -5, and 6. SOLVE IT THE SAME WAY AS A PRECAL WOULD -.i.e. using descartes rule of signs, synthetric division,upper bound and lower bound test, rational zero theorem, narrowing down choices using a ti-84 or ti-89 calcutior, or a combination of these methods. IMPORTANT NOTE: Our teacher we can't exclusively use the graphing calculator to determine the zeros of this function.

My work so far:

-plugged in 1 using synthetic devision, determined 1 was a zero. Then got decompressed function on bottom of synthetic division, x^3 -31x + 30.