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Statement-1 (Assertion and Statement- 2 ...

Statement-1 (Assertion and Statement- 2 (Reason)
Each of these questions also has four alternative
choices, only one of which is the correct answer. You
have to select the correct choice as given below.
Statement - 1 If A is skew-symnmetric matrix of order 3,
then its determinant should be zero.
Statement - 2 If A is square matrix,
`det (A) = det (A') = det (-A')`

A

Statement-1 is true, Statement -2 is true, Statement-2
is a correct explanation for Statement-1

B

Statement-1 is true, Statement-2 is true, Sttatement - 2
is not a correct explanation for Stamtement-1

C

Statement 1 is true, Statement - 2 is false

D

Statement-1 is false, Statement-2 is true

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze both statements provided in the question regarding a skew-symmetric matrix and the properties of determinants. ### Step 1: Analyze Statement 1 **Statement 1**: If \( A \) is a skew-symmetric matrix of order 3, then its determinant should be zero. 1. **Definition of Skew-Symmetric Matrix**: A matrix \( A \) is skew-symmetric if \( A^T = -A \). 2. **Property of Determinants**: We know that \( \text{det}(A) = \text{det}(A^T) \). 3. **Applying the Property**: Since \( A^T = -A \), we have: \[ \text{det}(A) = \text{det}(-A) \] 4. **Using the Determinant Property**: The determinant of a scalar multiple of a matrix is given by: \[ \text{det}(kA) = k^n \cdot \text{det}(A) \] where \( n \) is the order of the matrix. Here, \( k = -1 \) and \( n = 3 \): \[ \text{det}(-A) = (-1)^3 \cdot \text{det}(A) = -\text{det}(A) \] 5. **Setting up the Equation**: From the above, we have: \[ \text{det}(A) = -\text{det}(A) \] This implies: \[ 2 \cdot \text{det}(A) = 0 \implies \text{det}(A) = 0 \] 6. **Conclusion for Statement 1**: Therefore, Statement 1 is **true**. ### Step 2: Analyze Statement 2 **Statement 2**: If \( A \) is a square matrix, then \( \text{det}(A) = \text{det}(A^T) = \text{det}(-A^T) \). 1. **Property of Determinants**: For any square matrix \( A \), we know: \[ \text{det}(A) = \text{det}(A^T) \] This part of the statement is **true**. 2. **Analyzing \( \text{det}(-A^T) \)**: We have: \[ \text{det}(-A^T) = (-1)^n \cdot \text{det}(A^T) = (-1)^n \cdot \text{det}(A) \] where \( n \) is the order of the matrix. 3. **For Order 3**: Since \( n = 3 \): \[ \text{det}(-A^T) = -\text{det}(A) \] 4. **Conclusion for Statement 2**: The statement claims that \( \text{det}(A) = \text{det}(-A^T) \), which is not true because \( \text{det}(-A^T) = -\text{det}(A) \). Therefore, Statement 2 is **false**. ### Final Conclusion - **Statement 1** is **true**. - **Statement 2** is **false**.

To solve the problem, we need to analyze both statements provided in the question regarding a skew-symmetric matrix and the properties of determinants. ### Step 1: Analyze Statement 1 **Statement 1**: If \( A \) is a skew-symmetric matrix of order 3, then its determinant should be zero. 1. **Definition of Skew-Symmetric Matrix**: A matrix \( A \) is skew-symmetric if \( A^T = -A \). 2. **Property of Determinants**: We know that \( \text{det}(A) = \text{det}(A^T) \). 3. **Applying the Property**: Since \( A^T = -A \), we have: ...
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