Question 90613
if (x-1) and (x+4) are factors, then 1 and -4 are roots, making P(x)=0


P(1)=2(1)^3+5(1)^2-13(1)+4 ... P(1)=-2 ... 1 is not a root so (x-1) is not a factor


P(-4)=2(-4)^3+5(-4)^2-13(-4)+4 ... P(-4)=8 ... -4 is not a root so (x+4) is not a factor