Manu determines the roots of a polynomial equation p(x)=0 by applying the theorems he knows. he organizes the results of these theorems. from the fundamental theorems of algebra, manu knows there are 3 roots to the equation. from descartes' rule of sign, manu finds no sign changes in p(x) and 3 sign changes in p(-x). the rational root theorem yields +1/4,+1/2,+1,+5/4,+2,+5/2,+4,+5,+10 ,+20 as a list of possible rational roots. the lower bound of the polynomial is -6. the upper bound of the polynomial is 1. what values in manu's list of rational roots should he try in synthetic division in light of these findings?