CBSE Class 12 Mathematics 2026 Main Paper 65/5/1 · Q21 Marksidempotent_matrices
CBSE Class 12 Mathematics 2026 Main Paper 65/5/1 · Question 2 (Matrices)
If A²=A, find (A−I)³−A.
✅ Step-by-Step Solution
Final Answer: −I
- Since (I−A)²=I−A, its cube is I−A. Therefore (A−I)³=A−I and subtracting A leaves −I.
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