Processing Math: Done

Aus Online Mathematik Brückenkurs 2

A polynomial equation which has real coefficients always has complex conjugate roots. We can therefore say directly that the equation, in addition to the roots z=2i and z=−1+i, has roots z=2i=−2i and z=−1+i=−1−i. Because the equation is of degree 4, it does not have more than 4 roots.

The answer is thus

z=2i−2i−1+i−1−i.