Text Expand fully: (x+2)(x−1)(x+4).(x+2)(x-1)(x+4).(x+2)(x−1)(x+4). Solution First the two leading factors: (x+2)(x−1)=x2+x−2(x+2)(x-1)=x^{2}+x-2(x+2)(x−1)=x2+x−2. Then multiply by (x+4)(x+4)(x+4): (x2+x−2)(x+4)=x3+4x2+x2+4x−2x−8=x3+5x2+2x−8.(x^{2}+x-2)(x+4)=x^{3}+4x^{2}+x^{2}+4x-2x-8=x^{3}+5x^{2}+2x-8.(x2+x−2)(x+4)=x3+4x2+x2+4x−2x−8=x3+5x2+2x−8. x3+5x2+2x−8 \boxed{\,x^{3}+5x^{2}+2x-8\,}x3+5x2+2x−8