Question

Tính P_(x)

P_(x)=-80x⁶+80x⁵-80x⁴+...+80x+15 ; x=79

Answer 1

Ta có: x=79

nên x+1=80

\(P\left(x\right)=-x^6\left(x+1\right)+x^5\left(x+1\right)-x^4\left(x+1\right)+...+x\left(x+1\right)+15\)

\(=-x^7+x+15\)

\(=-79^7+94\)