Answer: Determinants of modified matrices.
- A Row reduction applied directly to the matrix
- B Matrix inverse multiplication, computed separately
- C Eigenvalues computed from the coefficient matrix
- D Determinants of modified matrices
Correct answer: D. Determinants of modified matrices
Explanation: Cramer's rule: xi = det(Ai) / det(A), where Ai is matrix A with the i-th column replaced by the constant vector B.
Concept context
Evaluation of determinants, cofactors, adjoint, inverse of matrix, Cramer's rule and area applications. Always in board and JEE.