b: x=-9 nên x-1=-10
\(B=x^4-x^3\left(x-1\right)-x^2\left(x-1\right)-x\left(x-1\right)-\left(x-1\right)\)
\(=x^4-x^4+x^3-x^3+x^2-x^2+x-x+1=1\)
c: x=9 nên x+1=10
\(C=x^{2017}-x^{2016}\left(x+1\right)+x^{2015}\left(x+1\right)-...-x^2\left(x+1\right)+x\left(x+1\right)-\left(x+1\right)\)
\(=x^{2017}-x^{2017}-x^{2016}+x^{2016}+...-x^3-x^2+x^2+x-x-1\)
=-1


