Let A and B be two symmetic matrices of order 3. Statement-1: A (BA) and (AB) A are symmetric matrices. Statement-2: AB is symmetric matrix if matrix multiplication of A and B is commutative. |
Statement-1 is True, Statement-2 is true; Statement-2 is a correct explanation for Statement-1. Statement-1 is True, Statement-2 is True; Statement-2 is not a correct explanation for Statement-1. Statement-1 is True, Statement-2 is False. Statement-1 is False, Statement-2 is True. |
Statement-1 is True, Statement-2 is True; Statement-2 is not a correct explanation for Statement-1. |
The correct answer is Option 2: Statement-1 is True, Statement-2 is True; Statement-2 is not a correct explanation for Statement-1. We have, $(A(BA))^T = (BA)^T A^T =(A^T B^T) A^T =(AB) A = A (BA)$ and, $((AB) A)^T = A^T (AB)^T = A^T (B^T A^T) = A (BA) = (AB) A$ $∴A (BA)$ and $(AB) A$ are symmetric matrices. So, statement-1 is true. If matrix multiplication of A and B is commutative. Then, $AB = BA$ $∴(AB)^T = B^T A^T = BA = AB$ $⇒ AB$ is symmetric matrix. Is Statement 2 the correct explanation for Statement 1? Statement 2 is not the correct explanation for Statement 1. While Statement 2 correctly says that the product AB will be symmetric only when AB=BA (i.e., when A and B commute), Statement 1 does not depend on this condition at all. In Statement 1, the matrices are of the form A(BA) and (AB)A, which simplify to ABA. This expression remains symmetric because A and B themselves are symmetric, regardless of whether they commute or not. Therefore, even if AB≠BA, Statement 1 still holds true. Hence, Statement 2, although correct on its own, does not explain Statement 1 |