Simple Complex Number Question (Roots of 1)

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The discussion centers on finding the complex fifth roots of one using Euler's equation, resulting in arguments of 0, 2pi/5, 4pi/5, 6pi/5, and 8pi/5. The original poster incorrectly expressed the roots as e^(i2pi/5) = 1^(1/5), which was pointed out as a misunderstanding since 1^(1/5) only represents the value 1, not all fifth roots of unity. The poster lost points for this error but correctly identified the roots. The advice given suggests that while the calculation of roots was accurate, the expression used was incorrect, leaving the decision to appeal up to the poster. Clarifying the distinction between the expressions is crucial for understanding complex roots.
bmb2009
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Homework Statement


So on one of my homework assignments I had to find the complex fifth roots of one. Because of Euler's equation the arguments are simply 0, 2pi/5,4pi/5,6pi/5,and 8pi/5. It is easy to see that (e^i2pi/5)^5 = (e^i2pi) = cos(2pi) + isin(2pi) = 1 + 0 = 1 but on my paper I wrote e^(i2pi/5) = 1^(1/5) and similar expressions for all the arguments of the fifth roots and lost 10 point out of 15. I wanted to ask the TA to regrade it but I don't want to bother him if I'm flat out wrong expressing the way I did? Any input would be great.. Thanks!


Homework Equations





The Attempt at a Solution

 
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bmb2009 said:

Homework Statement


So on one of my homework assignments I had to find the complex fifth roots of one. Because of Euler's equation the arguments are simply 0, 2pi/5,4pi/5,6pi/5,and 8pi/5. It is easy to see that (e^i2pi/5)^5 = (e^i2pi) = cos(2pi) + isin(2pi) = 1 + 0 = 1 but on my paper I wrote e^(i2pi/5) = 1^(1/5) and similar expressions for all the arguments of the fifth roots and lost 10 point out of 15. I wanted to ask the TA to regrade it but I don't want to bother him if I'm flat out wrong expressing the way I did? Any input would be great.. Thanks!

Homework Equations


The Attempt at a Solution


Saying e^(i2pi/5) = 1^(1/5) is flat out wrong. 1^(1/5) doesn't mean ANY fifth root of 1. It means 1. Saying (e^(i2pi/5))^5=1 is really what you meant. Still you got the roots. Up to you whether to appeal.
 
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