Answer: 1/4.
- A 4
- B 16
- C 0
- D 1/4
Correct answer: D. 1/4
Explanation: det(A<sup>-1</sup>) = 1/det(A) = 1/4. Since AA<sup>-1</sup> = I and det(I) = 1 = det(A) x det(A<sup>-1</sup>).
Concept context
Evaluation of determinants, cofactors, adjoint, inverse of matrix, Cramer's rule and area applications. Always in board and JEE.