CBSE Class 12 Mathematics 2026 Main Paper 65/3/3 · Q101 Marksdeterminant_scaling
CBSE Class 12 Mathematics 2026 Main Paper 65/3/3 · Question 10 (Determinants)
If A adj(A)=3I₃, find det(2A).
✅ Step-by-Step Solution
Final Answer: 24
- The adjugate identity gives det A=3. Scaling each of the three rows by 2 multiplies the determinant by 2³, giving 24.
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