Question 1104658
Two roots are 1-2i and r, and the given root is 1+2i.


If sum of these roots is 14 then  {{{(1+2i)+(1-2i)+r=14}}};
{{{r=12}}}.


{{{P(x)=(x-(1+2i))(x-(1-2i))(x-12)}}}
Do the simplification.

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{{{highlight(x^3-14x^2+29x-60)}}}