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If `alpha and beta` are the complex cube roots of unity, then what is the vlaue of `(1+alpha)(1+beta)(1+alpha^(2))(1+beta^(2))`?

A

`-1`

B

0

C

1

D

4

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of the expression \((1+\alpha)(1+\beta)(1+\alpha^2)(1+\beta^2)\), where \(\alpha\) and \(\beta\) are the complex cube roots of unity. ### Step-by-Step Solution: 1. **Identify the Cube Roots of Unity**: The complex cube roots of unity are given by: \[ 1, \quad \omega = e^{2\pi i / 3}, \quad \omega^2 = e^{-2\pi i / 3} \] where \(\omega\) and \(\omega^2\) are the non-real cube roots of unity. 2. **Properties of Cube Roots of Unity**: The cube roots of unity satisfy the equation: \[ 1 + \omega + \omega^2 = 0 \] and also: \[ \omega^3 = 1 \] Therefore, we can denote \(\alpha = \omega\) and \(\beta = \omega^2\). 3. **Substituting Values**: We need to evaluate: \[ (1+\omega)(1+\omega^2)(1+\omega^2)(1+\omega) \] This can be rewritten as: \[ (1+\omega)(1+\omega^2)^2 \] 4. **Calculating \(1+\omega\) and \(1+\omega^2\)**: We know: \[ 1+\omega = 1 + e^{2\pi i / 3} \quad \text{and} \quad 1+\omega^2 = 1 + e^{-2\pi i / 3} \] 5. **Using the Properties**: From the property \(1 + \omega + \omega^2 = 0\), we can express: \[ 1 + \omega^2 = -\omega \] and \[ 1 + \omega = -\omega^2 \] 6. **Substituting Back**: Now substituting these into our expression: \[ (1+\omega)(1+\omega^2) = (-\omega^2)(-\omega) = \omega^3 = 1 \] 7. **Final Calculation**: Therefore, we have: \[ (1+\alpha)(1+\beta)(1+\alpha^2)(1+\beta^2) = (1+\omega)(1+\omega^2)(1+\omega)(1+\omega^2) = 1 \cdot 1 = 1 \] ### Final Answer: The value of \((1+\alpha)(1+\beta)(1+\alpha^2)(1+\beta^2)\) is \(\boxed{1}\).

To solve the problem, we need to find the value of the expression \((1+\alpha)(1+\beta)(1+\alpha^2)(1+\beta^2)\), where \(\alpha\) and \(\beta\) are the complex cube roots of unity. ### Step-by-Step Solution: 1. **Identify the Cube Roots of Unity**: The complex cube roots of unity are given by: \[ 1, \quad \omega = e^{2\pi i / 3}, \quad \omega^2 = e^{-2\pi i / 3} ...
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