[tex]\begin{gathered} x^4-11x^2-18x-8\text{ has factor of (x+2) and (x+1) with multiplicity 2. This means that} \\ \text{the polynomial could be divided by} \\ (x+2)(x+1)^2=(x+2)(x^2+2x+1) \\ (x+2)(x+1)^2=x^3+2x^2+x+2x^2+4x+2 \\ (x+2)(x+1)^2=x^3+4x^2+5x+2 \end{gathered}[/tex][tex]\begin{gathered} from\text{ the synthetic division, we obtain that} \\ x^4-11x^2-18x-8=(x+2)(x+1)^2(x-4) \end{gathered}[/tex][tex]do\text{ you have questions?}[/tex]
