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Find the value of alphatimes(betatimesga...

Find the value of `alphatimes(betatimesgamma)`, where `alpha=2hat(i)-10hat(j)+2hat(k), beta=3hat(i)+hat(j)+2hat(k), gamma=2hat(i)+hat(j)+3hat(k)`.

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To find the value of \( \alpha \times (\beta \times \gamma) \), we will follow these steps: ### Step 1: Define the vectors Given: \[ \alpha = 2\hat{i} - 10\hat{j} + 2\hat{k} \] \[ \beta = 3\hat{i} + \hat{j} + 2\hat{k} \] \[ \gamma = 2\hat{i} + \hat{j} + 3\hat{k} \] ### Step 2: Calculate \( \beta \times \gamma \) To find \( \beta \times \gamma \), we will use the determinant of a matrix formed by the unit vectors \( \hat{i}, \hat{j}, \hat{k} \) and the components of \( \beta \) and \( \gamma \): \[ \beta \times \gamma = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \\ 3 & 1 & 2 \\ 2 & 1 & 3 \end{vmatrix} \] ### Step 3: Calculate the determinant Expanding the determinant, we have: \[ \beta \times \gamma = \hat{i} \begin{vmatrix} 1 & 2 \\ 1 & 3 \end{vmatrix} - \hat{j} \begin{vmatrix} 3 & 2 \\ 2 & 3 \end{vmatrix} + \hat{k} \begin{vmatrix} 3 & 1 \\ 2 & 1 \end{vmatrix} \] Calculating the 2x2 determinants: 1. \( \begin{vmatrix} 1 & 2 \\ 1 & 3 \end{vmatrix} = (1)(3) - (1)(2) = 3 - 2 = 1 \) 2. \( \begin{vmatrix} 3 & 2 \\ 2 & 3 \end{vmatrix} = (3)(3) - (2)(2) = 9 - 4 = 5 \) 3. \( \begin{vmatrix} 3 & 1 \\ 2 & 1 \end{vmatrix} = (3)(1) - (1)(2) = 3 - 2 = 1 \) Putting it all together: \[ \beta \times \gamma = \hat{i}(1) - \hat{j}(5) + \hat{k}(1) = \hat{i} - 5\hat{j} + \hat{k} \] ### Step 4: Calculate \( \alpha \times (\beta \times \gamma) \) Now we need to calculate \( \alpha \times (\beta \times \gamma) \): \[ \alpha \times (\beta \times \gamma) = \alpha \times (\hat{i} - 5\hat{j} + \hat{k}) \] Using the determinant: \[ \alpha \times (\beta \times \gamma) = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \\ 2 & -10 & 2 \\ 1 & -5 & 1 \end{vmatrix} \] ### Step 5: Calculate the determinant Expanding this determinant: \[ \alpha \times (\beta \times \gamma) = \hat{i} \begin{vmatrix} -10 & 2 \\ -5 & 1 \end{vmatrix} - \hat{j} \begin{vmatrix} 2 & 2 \\ 1 & 1 \end{vmatrix} + \hat{k} \begin{vmatrix} 2 & -10 \\ 1 & -5 \end{vmatrix} \] Calculating the 2x2 determinants: 1. \( \begin{vmatrix} -10 & 2 \\ -5 & 1 \end{vmatrix} = (-10)(1) - (2)(-5) = -10 + 10 = 0 \) 2. \( \begin{vmatrix} 2 & 2 \\ 1 & 1 \end{vmatrix} = (2)(1) - (2)(1) = 2 - 2 = 0 \) 3. \( \begin{vmatrix} 2 & -10 \\ 1 & -5 \end{vmatrix} = (2)(-5) - (-10)(1) = -10 + 10 = 0 \) Putting it all together: \[ \alpha \times (\beta \times \gamma) = \hat{i}(0) - \hat{j}(0) + \hat{k}(0) = 0 \] ### Final Answer Thus, the value of \( \alpha \times (\beta \times \gamma) \) is the zero vector: \[ \alpha \times (\beta \times \gamma) = \mathbf{0} \]
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