Understanding the Properties of Imaginary Cube Roots of Unity

AI Thread Summary
The roots of the equation x² + x + 1 = 0, denoted as α and β, are the imaginary cube roots of unity. When forming a quadratic equation with the roots α² and β², the sum and product of these roots yield the same original equation, x² + x + 1 = 0. Similarly, for the roots 1/α and 1/β, the calculations also lead to the same quadratic equation. This reflects the unique properties of the cube roots of unity, where squaring and taking reciprocals maintain the same relationships. The findings confirm that there is no error in the calculations presented.
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Homework Statement
Let the roots of x2 + x + 1 = 0 be \alpha and \beta, form a quadratic equation with roots:
(i) \alpha2, \beta2; and
(ii) \frac{1}{\alpha}, \frac{1}{\beta}.The attempt at a solution
sum of roots = \alpha + \beta = -1
product of roots = \alpha\beta = 1

(i)
sum of roots = \alpha2 + \beta2 = (-1)2 - 2(1) = -1
product of roots = \alpha2\beta2 = 12 = 1
Quadratic equation: x2 + x + 1 = 0

(ii)
sum of roots = \frac{1}{\alpha} + \frac{1}{\beta} = \frac{-1}{1} = -1
product of roots = (\frac{1}{\alpha})(\frac{1}{\beta}) = 1
Quadratic equation: x2 + x + 1 = 0

Is this weird? Did I do something wrong?
Thanks.
 
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correct.
roots of original equations are imaginary cube roots of unity.
which has the property that the square of first root is equal to second root,and square of second root is equal to first root.
the same property for taking reciprocals.
 
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