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If 1, omega and omega^(2) are the cube r...

If `1, omega` and `omega^(2)` are the cube roots of unity, then the value of `( 1+ omega) ( 1+ omega^(2)) ( 1+ omega^(4)) ( 1+ omega^(8))` is

A

`-1`

B

0

C

1

D

2

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The correct Answer is:
To solve the problem, we need to evaluate the expression \( (1 + \omega)(1 + \omega^2)(1 + \omega^4)(1 + \omega^8) \), where \( 1, \omega, \omega^2 \) are the cube roots of unity. ### Step-by-step Solution: 1. **Understanding Cube Roots of Unity**: The cube roots of unity are defined as the solutions to the equation \( x^3 = 1 \). The roots are \( 1, \omega, \omega^2 \) where: - \( \omega = e^{2\pi i / 3} \) - \( \omega^2 = e^{4\pi i / 3} \) Additionally, they satisfy the relations: - \( \omega^3 = 1 \) - \( 1 + \omega + \omega^2 = 0 \) 2. **Simplifying the Expression**: We need to simplify the expression \( (1 + \omega)(1 + \omega^2)(1 + \omega^4)(1 + \omega^8) \). 3. **Finding \( \omega^4 \) and \( \omega^8 \)**: Since \( \omega^3 = 1 \): - \( \omega^4 = \omega \) - \( \omega^8 = \omega^2 \) Thus, we can rewrite the expression as: \[ (1 + \omega)(1 + \omega^2)(1 + \omega)(1 + \omega^2) \] 4. **Combining Terms**: This can be simplified to: \[ (1 + \omega)^2 (1 + \omega^2)^2 \] 5. **Calculating \( (1 + \omega)(1 + \omega^2) \)**: We can compute: \[ (1 + \omega)(1 + \omega^2) = 1 + \omega + \omega^2 + \omega \cdot \omega^2 \] Since \( \omega \cdot \omega^2 = \omega^3 = 1 \), we have: \[ = 1 + \omega + \omega^2 + 1 = 2 + (\omega + \omega^2) \] Using \( 1 + \omega + \omega^2 = 0 \), we find: \[ \omega + \omega^2 = -1 \] Thus: \[ (1 + \omega)(1 + \omega^2) = 2 - 1 = 1 \] 6. **Final Calculation**: Now substituting back: \[ (1 + \omega)^2 (1 + \omega^2)^2 = 1^2 = 1 \] ### Conclusion: The value of \( (1 + \omega)(1 + \omega^2)(1 + \omega^4)(1 + \omega^8) \) is \( 1 \).
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