Complex numbers, where do I even start?!Watch this thread
I managed to get part a down (so being full of confidence had a go at part b, now I'm regretting it) so I can tell you part a has nothing to do with b/c
(hopefully the attachment works!)
to solve z^4 = -16, rewrite -16 as 16*(-1)= 16*e^i(π + 2kπ) , where k=0 ,1 ,2 and 3
Thereafter, If you quad root both sides,
you would arrive at
z = 2 *e^i [(π + 2kπ)/4]
You should be able to obtain the roots of the equation from this point onwards.
Hope it helps. Peace.