Sửa đề: \(x^{13}-6x^{12}+6x^{11}-6x^{10}+...-6x^2+6x-5\)
x=5 nên x+1=6
\(x^{13}-6x^{12}+6x^{11}-6x^{10}+...-6x^2+6x-5\)
\(=x^{13}-x^{12}\left(x+1\right)+x^{11}\left(x+1\right)-x^{10}\left(x+1\right)+...-x^2\left(x+1\right)+x\left(x+1\right)-x\)
\(=x^{13}-x^{13}-x^{12}+...-x^3-x^2+x^2+x-x\)
=0