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March 27th, 2013, 03:16 AM   #1
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complex numbers question

Could somebody please help me with this question?

A) solve z^5= 1 in polar form
I did that and found z=1, z=cis 2pi/5, z=cis -4pi/5, z= cis -2pi/5

The rest of the question perplexed me though;
B) describe how the solutions from A are related to the solutions of y^2=( 5+5^(1/2))/8 and
y^2=( 5- 5^(1/2))/8
I don't see the relation :/

C) use the information from A and B to write the exact value of sin 2pi/5.
I know how to find the exact value but not using the information in this question.

Any help would be greatly appreciated. Thank you
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March 27th, 2013, 01:48 PM   #2
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Re: complex numbers question

Can't help with B or C. For A you left out one solution. z = cis(4?/5).
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