Question 732260
Form a polynomial {{{f(x)}}} with real coefficients 
Degree: {{{4}}}; Zeros; {{{-1}}},{{{2}}} and {{{1}}}, {{{-2i}}}

use the zero product rule ...{{{f(x)=0}}}

{{{(x-x[1])(x-x[2])(x-x[3])(x-x[4])=0}}}...plug in {{{x[1]=-1}}},{{{x[2]=2}}}, {{{x[3]=1}}}, and {{{x[4]=-2i}}}


{{{(x-(-1))(x-2)(x-1)(x-(-2i))=0}}}


{{{(x+1)(x-2)(x-1)(x+2i)=0}}}


{{{(x^2-2x+x-2)(x^2+2xi-1x-2i)=0}}}


{{{(x^2-x-2)(x^2+2xi-2i-1x)=0}}}


{{{(x^2-x-2)(x^2+2i(x-1)-1x)=0}}}


{{{x^4-(2-2i)x^3-(1+4i)x^2+(2-2i)x+4i=0}}}

or

{{{f(x)=x^4-(2-2i)x^3-(1+4i)x^2+(2-2i)x+4i}}}