Question 1160230
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<pre>

The magnitude = {{{sqrt((-3)^2 + (-4)^2)}}} = {{{sqrt(25)}}} = 5.


To find square roots, I will make this trick


    -3 - 4i = 1 - 4i -4 = complete the square = (1-2i)^2.


Therefore, the square roots of  (-3-4i)  are these two complex numbers


    (1-2i)  and  -(1-2i) = -1+2i.
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Solved.