SOLUTION: Find all complex z which solve z^9=-1 My attempt consists in changing it to polar form..but I really don't understand how to do it!

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Question 694506: Find all complex z which solve z^9=-1
My attempt consists in changing it to polar form..but I really don't understand how to do it!
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find all complex z which solve z^9=-1
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Use DeMoivre's Theorem
z^9 = -1 = 1cis(180 + n*360)
z = 1cis(20)
z = 1cis(60)
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z = 1cis(20 + n*40) n = 0 to 8