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Let I, omega and omega^(2) be the cube ...

Let I, `omega` and `omega^(2)` be the cube roots of unity. The least possible degree of a polynomial, with real coefficients having `2omega^(2), 3 + 4 omega, 3 + 4 omega^(2) ` and `5- omega - omega^(2)` as roots is -

A

`4`

B

`5`

C

`6`

D

`7`

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To find the least possible degree of a polynomial with real coefficients that has the given roots \(2\omega^2\), \(3 + 4\omega\), \(3 + 4\omega^2\), and \(5 - \omega - \omega^2\), we will follow these steps: ### Step 1: Identify the roots The roots provided are: 1. \(2\omega^2\) 2. \(3 + 4\omega\) 3. \(3 + 4\omega^2\) 4. \(5 - \omega - \omega^2\) ### Step 2: Use properties of cube roots of unity Recall that the cube roots of unity are \(1\), \(\omega\), and \(\omega^2\), where: \[ \omega + \omega^2 + 1 = 0 \quad \Rightarrow \quad \omega + \omega^2 = -1 \] This means \(\omega^2 = -1 - \omega\) and \(\omega = -1 - \omega^2\). ### Step 3: Find conjugate roots Since the polynomial must have real coefficients, the complex roots must occur in conjugate pairs. - If \(2\omega^2\) is a root, then \(2\omega\) must also be a root because \(\omega\) and \(\omega^2\) are conjugates. - The roots \(3 + 4\omega\) and \(3 + 4\omega^2\) are already conjugate pairs. - The root \(5 - \omega - \omega^2\) can be simplified using the property of cube roots: \[ 5 - \omega - \omega^2 = 5 - (-1) = 6 \] Thus, \(6\) is also a root. ### Step 4: List all the roots Now we have the following roots: 1. \(2\omega^2\) 2. \(2\omega\) 3. \(3 + 4\omega\) 4. \(3 + 4\omega^2\) 5. \(6\) ### Step 5: Count the distinct roots We have identified 5 distinct roots: - \(2\omega\) - \(2\omega^2\) - \(3 + 4\omega\) - \(3 + 4\omega^2\) - \(6\) ### Step 6: Determine the degree of the polynomial A polynomial with \(n\) distinct roots has a degree of \(n\). Since we have 5 distinct roots, the least possible degree of the polynomial is: \[ \text{Degree} = 5 \] ### Final Answer The least possible degree of the polynomial with the given roots is **5**. ---

To find the least possible degree of a polynomial with real coefficients that has the given roots \(2\omega^2\), \(3 + 4\omega\), \(3 + 4\omega^2\), and \(5 - \omega - \omega^2\), we will follow these steps: ### Step 1: Identify the roots The roots provided are: 1. \(2\omega^2\) 2. \(3 + 4\omega\) 3. \(3 + 4\omega^2\) 4. \(5 - \omega - \omega^2\) ...
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