Question

Answer 1

Ta có: \(x=79\Rightarrow x-79=0\)

\(B\left(x\right)=\left(x^7-79x^6\right)+\left(-x^6+79x^5\right)+\left(x^5-79x^4\right)+...+\left(-x^2+79x\right)+x+15\)

\(=x^6\left(x-79\right)-x^5\left(x-79\right)+x^4\left(x-79\right)+...-x\left(x-79\right)+79+15\)

\(=94\)