CBSE Class 12 Mathematics 2026 Main Paper 65/3/1 · Q61 Marksadjugate
CBSE Class 12 Mathematics 2026 Main Paper 65/3/1 · Question 6 (Determinants)
If B adj(B)=(1/3)I₃, find det(B⁻¹).
✅ Step-by-Step Solution
Final Answer: 3
- Use B adj(B)=det(B)I, so det(B)=1/3. The determinant of the inverse is the reciprocal, 3.
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