Answer
$x^3-4x^2+6x-4$
Work Step by Step
We need to write down the polynomial $f(x)$ in factored form.
$f(x)=(x-2)[x-(1+i)][x-(1-i)]$
$=(x-2)(x-1-i)(x-1+i)$
$=(x-2)(x^2-x+xi-x+1-i-xi+i-i^2)$
$=(x-2)(x^2-2x+2)$\
$=x^3-2x^2+2x-2x^2+4x-4$
$=x^3-4x^2+6x-4$