해결방법 - PolynomialRootFinder

$$factors\left(\left|a_0\right|\right)=1,2,4,5,10,20,25,50,100,125,250,500$$

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

$$x=+/-p/q=-1,1,-2,2,-4,4,-5,5,-10,10,-20,20,-25,25,-50,50,-100,100,-125,125,-250,250,-500,500$$

$$P\left(-1\right)=486$$

$$P\left(1\right)=484$$

$$P\left(-2\right)=448$$

$$P\left(2\right)=432$$

$$P\left(-4\right)=324$$

$$P\left(4\right)=196$$

$$P\left(-5\right)=250$$

$$P\left(5\right)=0$$

$$\left(x-5\right)\left(-x^2-20x-100\right)=0$$

$$x=-10,-10$$