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If omega is the imaginary cube root of ...

If `omega` is the imaginary cube root of unity, then what is `(2-omega+2omega^(2))^(27)` equal to ?

A

`3^(27)omega`

B

`-3^(27)omega^(2)`

C

`3^(27)`

D

`-3^(27)`

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AI Generated Solution

The correct Answer is:
To solve the problem \( (2 - \omega + 2\omega^2)^{27} \) where \( \omega \) is the imaginary cube root of unity, we can follow these steps: ### Step 1: Understand the properties of cube roots of unity The cube roots of unity are \( 1, \omega, \) and \( \omega^2 \), where: - \( \omega = e^{2\pi i / 3} \) - \( \omega^2 = e^{-2\pi i / 3} \) - The key property is that \( 1 + \omega + \omega^2 = 0 \) and \( \omega^3 = 1 \). ### Step 2: Simplify the expression inside the parentheses We start with: \[ 2 - \omega + 2\omega^2 \] Using the identity \( 1 + \omega + \omega^2 = 0 \), we can express \( \omega^2 \) in terms of \( \omega \): \[ \omega^2 = -1 - \omega \] Substituting this into the expression gives: \[ 2 - \omega + 2(-1 - \omega) = 2 - \omega - 2 - 2\omega = -3\omega \] ### Step 3: Raise the simplified expression to the power of 27 Now we have: \[ (-3\omega)^{27} \] Using the property of exponents: \[ (-3)^{27} \cdot \omega^{27} \] ### Step 4: Simplify \( \omega^{27} \) Since \( \omega^3 = 1 \), we can reduce the exponent modulo 3: \[ 27 \mod 3 = 0 \quad \Rightarrow \quad \omega^{27} = (\omega^3)^9 = 1^9 = 1 \] ### Step 5: Combine the results Thus, we have: \[ (-3)^{27} \cdot 1 = -3^{27} \] ### Final Answer The final result is: \[ (2 - \omega + 2\omega^2)^{27} = -3^{27} \] ---

To solve the problem \( (2 - \omega + 2\omega^2)^{27} \) where \( \omega \) is the imaginary cube root of unity, we can follow these steps: ### Step 1: Understand the properties of cube roots of unity The cube roots of unity are \( 1, \omega, \) and \( \omega^2 \), where: - \( \omega = e^{2\pi i / 3} \) - \( \omega^2 = e^{-2\pi i / 3} \) - The key property is that \( 1 + \omega + \omega^2 = 0 \) and \( \omega^3 = 1 \). ...
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