Question

If f(a) = 23 - 207 - 732 - 70, which of the following is not a factor of f(z)?

Answer 1

`f(x)=x^3-2x^2-73x-70^{}`
`f(x)=x^3+x^2-3x^2-3x-70x-70\Rightarrow f(x)=x^2(x+1)-3x(x+1)-70(x+1)\Rightarrow f(x)=(x+1)(x^2-3x-70)\Rightarrow f(x)=(x+1)(x-10)(x+7)_{}`

Hence

`f(x)=(x+1)(x-10)(x+7)`

Hence (x+10) is not a factor of f(x).