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CBSE Class 12 Mathematics 2026 Main Paper 65/3/1 · Q21 Marksmatrix_inverse

CBSE Class 12 Mathematics 2026 Main Paper 65/3/1 · Question 2 (Matrices)

If A²=4A+3I and A⁻¹=xA+yI, find x+y from the inverse expression obtained using the matrix identity.

✅ Step-by-Step Solution

Final Answer: −1
  1. Multiply A²−4A=3I by A⁻¹ to get A⁻¹=(1/3)A−(4/3)I. These coefficients sum to −1.

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All Questions in CBSE Class 12 Mathematics 2026 Main Paper 65/3/1

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