-(x^4-1/2x^3-1/2)÷(x-1)=-(x^4-x^3+1/2x^3-1/2x^2+1/2x^2-1/2x+1/2x-1/2)÷(x-1)=-[(x^4-x^3)÷(x-1)+(1/2x^3-1/2x^2)÷(x-1)+(1/2x^2-1/2x)÷(x-1)+(1/2x-1/2)÷(x-1)]=-(x^3+1/2x^2+1/2x+1/2)=-x^3-1/2x^2-1/2x-...