Answer: non-zero.
- A non-zero
- B zero
- C positive
- D negative
Correct answer: A. non-zero
Explanation: Cramer’s rule requires the coefficient determinant D ≠ 0 for a unique solution.
Concept context
Evaluation of determinants, cofactors, adjoint, inverse of matrix, Cramer's rule and area applications. Always in board and JEE.