Class 12 Determinants · Conceptual Answer1 Marksadjugate
Class 12 Maths · Determinants · Conceptual Answer #41
For a 2×2 matrix A, A adj(A)=8I. Find det(A).
✅ Step-by-Step Solution
Final Answer: 8
- The adjugate identity gives A adj(A)=det(A)I, so matching diagonal entries gives det(A)=8.
- 8
📋 CBSE Stepwise Marking Scheme
- [0.5 marks] The adjugate identity gives A adj(A)=det(A)I, so matching diagonal entries gives det(A)=8.
- [0.5 marks] 8
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