해결방법 - PolynomialRootFinder

$$factors\left(\left|a_0\right|\right)=1,2,3,4,6,8,9,12,18,24,36,72$$

$$factors\left(\left|a_n\right|\right)=1,2$$

$$x=+/-p/q=-1/2,1/2,-1,1,-3/2,3/2,-2,2,-3,3,-4,4,-9/2,9/2,-6,6,-8,8,-9,9,-12,12,-18,18,-24,24,-36,36,-72,72$$

$$P\left(-1/2\right)=-80.75$$

$$P\left(1/2\right)=-72.25$$

$$P\left(-1\right)=-100$$

$$P\left(1\right)=-80$$

$$P\left(-3/2\right)=-131.25$$

$$P\left(3/2\right)=-93.75$$

$$P\left(-2\right)=-176$$

$$P\left(2\right)=-112$$

$$P\left(-3\right)=-312$$

$$P\left(3\right)=-156$$

$$\left(x-9\right)\left(2x^2+8\right)=0$$

$$x=-2i,2i$$