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Let A be a 3xx3 determinant and |A|=7. T...

Let A be a `3xx3` determinant and `|A|=7`. Then the value of `|2A|` is.............

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To find the value of \(|2A|\) where \(|A| = 7\) and \(A\) is a \(3 \times 3\) determinant, we can use the property of determinants related to scalar multiplication. ### Step-by-step Solution: 1. **Understand the property of determinants**: For any scalar \(k\) and an \(n \times n\) matrix \(A\), the determinant of \(kA\) is given by: \[ |kA| = k^n |A| \] where \(n\) is the order of the matrix. 2. **Identify the values**: In this case, \(k = 2\) (since we are calculating \(|2A|\)), and the order \(n = 3\) (since \(A\) is a \(3 \times 3\) matrix). 3. **Apply the property**: Substitute the values into the property: \[ |2A| = 2^3 |A| \] 4. **Calculate \(2^3\)**: \[ 2^3 = 8 \] 5. **Substitute the value of \(|A|\)**: We know that \(|A| = 7\), so: \[ |2A| = 8 \times 7 \] 6. **Perform the multiplication**: \[ |2A| = 56 \] Thus, the value of \(|2A|\) is **56**.
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