Consider the following statements: Statement-I: If X is an n \times n matrix, then \det(mX)=m^n \det(X), where m is a scalar. Statement-II: If Y is a matrix obtained from X by multiplying any row or column by a scalar m, then \det(Y)=m \det(X). Which one of the following is correct in respect of the above statements?

  1. A. Both Statement-I and Statement-II are correct and Statement-II explains Statement-I
  2. B. Both Statement-I and Statement-II are correct but Statement-II does not explain Statement-I
  3. C. Statement-I is correct but Statement-II is not correct
  4. D. Statement-I is not correct but Statement-II is correct

Correct Answer: A. Both Statement-I and Statement-II are correct and Statement-II explains Statement-I

Explanation

Statement-II provides a fundamental property of determinants (factoring out a scalar from a single row/column). Statement-I is a direct consequence of applying Statement-II n times (once for each of the n rows) when the entire matrix is scaled by m. Thus, both are correct, and II explains I.

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