Plotting the roots of unity on the complex plane

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SUMMARY

The discussion focuses on finding the 6th complex roots of the number √3 + i, which can be expressed in polar form as z^6 = 2(cos(π/6) + isin(π/6)). The roots are calculated using the formula z = 2^(1/6)(cos(θ) + isin(θ)), where θ is determined by the equation 6θ = π/6 + 2kπ for k = 0 to 5. The roots are evenly distributed around the unit circle, with each root separated by an angle of π/3 radians. The participant seeks clarification on whether all roots of unity have the same positions on the complex plane, which is confirmed to be true for evenly spaced roots.

PREREQUISITES
  • Understanding of complex numbers and their polar representation
  • Familiarity with De Moivre's Theorem
  • Knowledge of trigonometric functions and their properties
  • Basic skills in plotting points on the complex plane
NEXT STEPS
  • Learn about De Moivre's Theorem and its applications in finding roots of complex numbers
  • Explore the concept of roots of unity and their geometric interpretations
  • Study polar coordinates and their conversion to Cartesian coordinates
  • Investigate software tools for plotting complex functions, such as Python's Matplotlib or MATLAB
USEFUL FOR

Mathematics students, educators, and anyone interested in complex analysis or graphical representations of complex numbers will benefit from this discussion.

Cottontails
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Homework Statement


Find the 6th complex roots of √3 + i.

Homework Equations


z^6=2(cos(π/6)+isin(π/6))
r^6=2, r=2^1/6
6θ=π/6+2kπ, θ=π/36+kπ/3

The Attempt at a Solution


When k=0, z = 2^1/6(cos(π/36)+isin(π/36)),
When k=1, z = 2^1/6(cos(13π/36)+isin(13π/36)),
When k=2, z = 2^1/6(cos(25π/36)+isin(25π/36)),
When k=3, z = 2^1/6(cos(37π/36)+isin(37π/36)),
When k=4, z = 2^1/6(cos(49π/36)+isin(49π/36)),
When k=5, z = 2^1/6(cos(61π/36)+isin(61π/36)).
I just want help with plotting these roots on the complex plane. So, I am just wondering, are all roots of unity on the complex plane the same, regardless of the equation? By this, I mean, are the position of the roots the same, regardless of what the equation is?
 
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Cottontails said:

Homework Statement


Find the 6th complex roots of √3 + i.

Homework Equations


z^6=2(cos(π/6)+isin(π/6))
r^6=2, r=2^1/6
6θ=π/6+2kπ, θ=π/36+kπ/3

The Attempt at a Solution


When k=0, z = 2^1/6(cos(π/36)+isin(π/36)),
When k=1, z = 2^1/6(cos(13π/36)+isin(13π/36)),
When k=2, z = 2^1/6(cos(25π/36)+isin(25π/36)),
When k=3, z = 2^1/6(cos(37π/36)+isin(37π/36)),
When k=4, z = 2^1/6(cos(49π/36)+isin(49π/36)),
When k=5, z = 2^1/6(cos(61π/36)+isin(61π/36)).
I just want help with plotting these roots on the complex plane. So, I am just wondering, are all roots of unity on the complex plane the same, regardless of the equation? By this, I mean, are the position of the roots the same, regardless of what the equation is?

These aren't the roots of unity. They are the roots of ##\sqrt 3 +i##. I'm not sure what you mean by the position being the same. What they are is distributed evenly around the circle. In this example, each one is rotated ##\frac \pi 3## from the next, so by the time you do that 6 times, you are all the way around.
 

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