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Complex numbers question! (Roots of equation)

The question is 15iii on here: http://www.dur.ac.uk/c.c.d.s.caiado/wbook2012.pdf

"Use part ii to find the three distinct roots of the equation z3=1z^3=1. Draw them on the complex plane and convert them from modulus-argument form to real-imaginary form."

In part ii I showed that re(iθ) re^ (i\theta) =1 (for real theta and r>0) if and only if r=1 and theta=2.n.pi for some integer n..

Thanks, any ideas would be much appreciated! (+rep)
(edited 11 years ago)
Reply 1
You know we can write any z in the form reiθr e^{i\theta}. So if z=reiθz = r e^{i\theta}, what is z^3? Now use part (ii)

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