Complex number: Roots 
Solve all the roots of the following equation: $$(z-i)^2(z+i)^2=\frac{1}{4}.$$ Find the set of complex numbers $z$ such that $$\left|\frac{z-3}{z+3}\right|=2.$$

Would anyone mind telling me how to solve the above problems? I really have no idea.

For the first question, you have $(z-i)(z +i) = z^2 + 1$.  This should help you get there.
For the second, you might want to square both sides and clear the fraction.  
Try these things and see if they help.
