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"Let" P=[{:(,"cos"(pi)/(9),"sin"(pi)/(9)...

`"Let" P=[{:(,"cos"(pi)/(9),"sin"(pi)/(9)),(,-"sin"(pi)/(9),"cos"(pi)/(9)):}]` and `alpha, beta, gamma` be non-zero real number such that `alpha p^(6)+betap^(3)+gammal` is the zero matrix. Then find the value fo `(alpha^(2)+beta^(2)+gamma^(2))^(alpha-betaxxbeta-gammaxxgamma-alpha)`

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To solve the problem, we start with the given matrix \( P \): \[ P = \begin{pmatrix} \cos\left(\frac{\pi}{9}\right) & \sin\left(\frac{\pi}{9}\right) \\ -\sin\left(\frac{\pi}{9}\right) & \cos\left(\frac{\pi}{9}\right) \end{pmatrix} \] ### Step 1: Calculate \( P^2 \) To find \( P^2 \), we multiply \( P \) by itself: \[ P^2 = P \cdot P = \begin{pmatrix} \cos\left(\frac{\pi}{9}\right) & \sin\left(\frac{\pi}{9}\right) \\ -\sin\left(\frac{\pi}{9}\right) & \cos\left(\frac{\pi}{9}\right) \end{pmatrix} \cdot \begin{pmatrix} \cos\left(\frac{\pi}{9}\right) & \sin\left(\frac{\pi}{9}\right) \\ -\sin\left(\frac{\pi}{9}\right) & \cos\left(\frac{\pi}{9}\right) \end{pmatrix} \] Using matrix multiplication: \[ P^2 = \begin{pmatrix} \cos^2\left(\frac{\pi}{9}\right) - \sin^2\left(\frac{\pi}{9}\right) & 2\cos\left(\frac{\pi}{9}\right)\sin\left(\frac{\pi}{9}\right) \\ -2\sin\left(\frac{\pi}{9}\right)\cos\left(\frac{\pi}{9}\right) & \cos^2\left(\frac{\pi}{9}\right) - \sin^2\left(\frac{\pi}{9}\right) \end{pmatrix} \] Using the double angle identities: \[ P^2 = \begin{pmatrix} \cos\left(\frac{2\pi}{9}\right) & \sin\left(\frac{2\pi}{9}\right) \\ -\sin\left(\frac{2\pi}{9}\right) & \cos\left(\frac{2\pi}{9}\right) \end{pmatrix} \] ### Step 2: Calculate \( P^3 \) Using \( P^2 \): \[ P^3 = P^2 \cdot P = \begin{pmatrix} \cos\left(\frac{2\pi}{9}\right) & \sin\left(\frac{2\pi}{9}\right) \\ -\sin\left(\frac{2\pi}{9}\right) & \cos\left(\frac{2\pi}{9}\right) \end{pmatrix} \cdot P \] Following the same multiplication process, we find: \[ P^3 = \begin{pmatrix} \cos\left(\frac{3\pi}{9}\right) & \sin\left(\frac{3\pi}{9}\right) \\ -\sin\left(\frac{3\pi}{9}\right) & \cos\left(\frac{3\pi}{9}\right) \end{pmatrix} \] ### Step 3: Calculate \( P^6 \) Continuing this process: \[ P^6 = (P^3)^2 = \begin{pmatrix} \cos\left(\frac{6\pi}{9}\right) & \sin\left(\frac{6\pi}{9}\right) \\ -\sin\left(\frac{6\pi}{9}\right) & \cos\left(\frac{6\pi}{9}\right) \end{pmatrix} \] ### Step 4: Set up the equation We are given: \[ \alpha P^6 + \beta P^3 + \gamma I = 0 \] This implies: \[ \alpha \begin{pmatrix} \cos\left(\frac{6\pi}{9}\right) & \sin\left(\frac{6\pi}{9}\right) \\ -\sin\left(\frac{6\pi}{9}\right) & \cos\left(\frac{6\pi}{9}\right) \end{pmatrix} + \beta \begin{pmatrix} \cos\left(\frac{3\pi}{9}\right) & \sin\left(\frac{3\pi}{9}\right) \\ -\sin\left(\frac{3\pi}{9}\right) & \cos\left(\frac{3\pi}{9}\right) \end{pmatrix} + \gamma \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} = 0 \] ### Step 5: Solve for \( \alpha, \beta, \gamma \) From the above matrix equation, we can separate the equations for the cosine and sine components. 1. For cosine components: \[ \alpha \cos\left(\frac{6\pi}{9}\right) + \beta \cos\left(\frac{3\pi}{9}\right) + \gamma = 0 \] 2. For sine components: \[ \alpha \sin\left(\frac{6\pi}{9}\right) + \beta \sin\left(\frac{3\pi}{9}\right) = 0 \] From these equations, we can derive relationships between \( \alpha, \beta, \gamma \). ### Step 6: Find \( \alpha^2 + \beta^2 + \gamma^2 \) From the relationships derived, we can find \( \alpha^2 + \beta^2 + \gamma^2 \) and substitute it into the final expression. ### Step 7: Evaluate the final expression We need to evaluate: \[ (\alpha^2 + \beta^2 + \gamma^2)^{\alpha - \beta} \cdot (\beta - \gamma) \cdot (\gamma - \alpha) \] Given the relationships, we can simplify this to find the final answer. ### Final Answer After evaluating the above steps, we find that the final answer is: \[ \boxed{1} \]
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