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For a rectangle base is (hat(i) + hat(j)...

For a rectangle base is `(hat(i) + hat(j) + hat(k))` and adjacent side is `(4 hat(j) + 3hat(k))`. If the area of rectangle is `5^(n)` then value of n is

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To solve the problem, we need to find the area of a rectangle given its base and adjacent side vectors. Let's break down the steps: ### Step 1: Define the vectors Let: - **Base vector** \( \mathbf{a} = \hat{i} + \hat{j} + \hat{k} \) - **Adjacent side vector** \( \mathbf{b} = 4\hat{j} + 3\hat{k} \) ### Step 2: Calculate the cross product \( \mathbf{a} \times \mathbf{b} \) The area of the rectangle can be found using the magnitude of the cross product of the two vectors. We will use the determinant method to calculate \( \mathbf{a} \times \mathbf{b} \). \[ \mathbf{a} \times \mathbf{b} = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \\ 1 & 1 & 1 \\ 0 & 4 & 3 \end{vmatrix} \] ### Step 3: Expand the determinant Using the determinant expansion, we have: \[ \mathbf{a} \times \mathbf{b} = \hat{i} \begin{vmatrix} 1 & 1 \\ 4 & 3 \end{vmatrix} - \hat{j} \begin{vmatrix} 1 & 1 \\ 0 & 3 \end{vmatrix} + \hat{k} \begin{vmatrix} 1 & 1 \\ 0 & 4 \end{vmatrix} \] Calculating the 2x2 determinants: 1. For \( \hat{i} \): \[ \begin{vmatrix} 1 & 1 \\ 4 & 3 \end{vmatrix} = (1)(3) - (1)(4) = 3 - 4 = -1 \] 2. For \( \hat{j} \): \[ \begin{vmatrix} 1 & 1 \\ 0 & 3 \end{vmatrix} = (1)(3) - (1)(0) = 3 - 0 = 3 \] 3. For \( \hat{k} \): \[ \begin{vmatrix} 1 & 1 \\ 0 & 4 \end{vmatrix} = (1)(4) - (1)(0) = 4 - 0 = 4 \] Putting it all together: \[ \mathbf{a} \times \mathbf{b} = -\hat{i} - 3\hat{j} + 4\hat{k} \] ### Step 4: Calculate the magnitude of the cross product Now, we find the magnitude of \( \mathbf{a} \times \mathbf{b} \): \[ |\mathbf{a} \times \mathbf{b}| = \sqrt{(-1)^2 + (-3)^2 + (4)^2} = \sqrt{1 + 9 + 16} = \sqrt{26} \] ### Step 5: Set the area equal to \( 5^n \) We know that the area of the rectangle is given as: \[ \text{Area} = |\mathbf{a} \times \mathbf{b}| = \sqrt{26} \] We are given that this area equals \( 5^n \): \[ \sqrt{26} = 5^n \] ### Step 6: Solve for \( n \) To solve for \( n \), we can take logarithms: \[ \log(\sqrt{26}) = n \log(5) \] This simplifies to: \[ \frac{1}{2} \log(26) = n \log(5) \] Thus, we can isolate \( n \): \[ n = \frac{\frac{1}{2} \log(26)}{\log(5)} = \frac{\log(26)}{2 \log(5)} \] ### Conclusion The value of \( n \) is: \[ n = \frac{\log(26)}{2 \log(5)} \]
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