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    z^5=4-4i
    a) Solve this equation, giving your solutions in the form re^iϴ
    b) Display these solutions on an argand diagram
    c) Deduce that lpl=2sin(π/5) where p=e^(3πi/4)-e^(7πi/20)

    Now I've done part a) and b) and I know I'm correct on those questions. In case you're wodering my solutions to a were:
    z=√2e^(-πi/20)
    z=√2e^(7πi/20)
    z=√2e^(-9πi/20)
    z=√2e^(3πi/4)
    z=√2e^(-17πi/20)

    I know that part c) is definetely related to part a), but I haven't got the slightest clue how to solve it algebraically. Could anyone please give me a hand and point me in the right direction?
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    okay I've worked it out. In terms of clues, use your answer to (b) to solve it geometrically. Just shout if you want a pic of my workings
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    (Original post by Darth_Narwhale)
    okay I've worked it out. In terms of clues, use your answer to (b) to solve it geometrically. Just shout if you want a pic of my workings
    Just solved it now. Didn't realise I had to use C3 knowledge what with double angle formulae and such. Thanks anyway!
 
 
 
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Updated: January 16, 2017

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