Question 798748

{{{(x+4)(x-(2+i))(x-(2-i))}}}.....good start, now just multiply

{{{(x+4)(x-2-i)(x-2+i)}}}


{{{(x^2-2x-xi+4x-8-4i)(x-2+i)}}}


{{{(x^2+2x-xi-4i-8)(x-2+i)}}}


{{{x^3+2x^2-x^2i-4xi-8x-2x^2-2x+2xi+8i+16+x^2i+2xi+xi^2-4i^2-8i }}}


{{{x^3+cross(2x^2)-cross(x^2i)-cross(4xi)-8x-cross(2x^2)-2x+cross(4xi)+cross(8i)+16+cross(x^2i) +xi^2-4i^2-cross(8i) }}}


{{{x^3-10x +16 +x(-1) -4(-1)  }}}....recall that {{{i^2=-1}}}



{{{x^3-10x +16-x +4  }}}

{{{x^3-11x +20  }}}.........your answer


{{{ graph( 600, 600, -10, 10, -10, 30, x^3-11x +20 ) }}}