Question 1201671
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<pre>

Since (1+i) is a root, the conjugate (1-i) is the root, too.


Using Vieta's theorem, we can write then that the sum of the roots is {{{-(-5)/2)}}} = {{{5/2}}}


    (1+i) + (1-i) + r = {{{5/2}}},   where "r" is the third root,

or

    2 + r = {{{5/2}}},  r = {{{5/2}}} - 2 = {{{1/2}}}.    <U>ANSWER</U>
</pre>

Solved.